From HoTT Require Import Basics Types.From HoTT Require Import Basics Types.
Require Import WildCat.Core WildCat.Coproducts.
Require Import Cubical.DPath.
Require Import Spaces.List.Core Spaces.List.Theory.
Require Import Colimits.Pushout.
Require Import Truncations.Core Truncations.SeparatedTrunc.
Require Import Algebra.Groups.Group.

Local Open Scope list_scope.
Local Open Scope mc_scope.
Local Open Scope mc_mult_scope.

(** In this file we define the amalgamated free product of a span of group homomorphisms as a HIT. *)

(** We wish to define the amalgamated free product of a span of group homomorphisms f : G -> H, g : G -> K as the following HIT:

<<
  HIT M(f,g)
   | amal_eta : list (H + K) -> M(f,g)
   | mu_H : forall (x y : list (H + K)) (h1 h2 : H),
      amal_eta (x ++ [inl h1, inl h2] ++ y) = amal_eta (x ++ [inl (h1 * h2)] ++ y)
   | mu_K : forall (x y : list (H + K)) (k1 k2 : K),
      amal_eta (x ++ [inr k1, inr k2] ++ y) = amal_eta (x ++ [inr (k1 * k2)] ++ y)
   | tau : forall (x y : list (H + K)) (z : G),
      amal_eta (x ++ [inl (f z)] ++ y) = amal_eta (x ++ [inr (g z)] ++ y)
   | omega_H : forall (x y : list (H + K)),
      amal_eta (x ++ [inl mon_unit] ++ y) = amal_eta (x ++ y)
   | omega_K : forall (x y : list (H + K)),
      amal_eta (x ++ [inr mon_unit] ++ y) = amal_eta (x ++ y).
>>

  We will build this HIT up successively out of coequalizers. *)

(** We will call M [amal_type] and prefix all the constructors with [amal_] (for amalgamated free product). *)

Section AmalgamatedFreeProduct.

  Context {G H K : Group}
    (f : GroupHomomorphism G H) (g : GroupHomomorphism G K).

  Local Definition Words : Type := list (H + K).

  Local Fixpoint word_inverse (x : Words) : Words.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
word_inverse: Words -> Words
x: Words
Words
  Proof.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
word_inverse: Words -> Words
x: Words
Words
    destruct x as [|x xs].
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
word_inverse: Words -> Words
Words
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
word_inverse: Words -> Words
x: H + K
xs: list (H + K)
Words
    1: exact nil.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
word_inverse: Words -> Words
x: H + K
xs: list (H + K)
Words
    destruct x as [h|k].
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
word_inverse: Words -> Words
h: H
xs: list (H + K)
Words
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
word_inverse: Words -> Words
k: K
xs: list (H + K)
Words
    +
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
word_inverse: Words -> Words
h: H
xs: list (H + K)
Words exact ((word_inverse xs) ++ [inl h^]).
    +
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
word_inverse: Words -> Words
k: K
xs: list (H + K)
Words exact ((word_inverse xs) ++ [inr k^]).
  Defined.

  (** Inversion changes order of concatenation. *)
  Local Definition word_inverse_ww (x y : Words)
    : word_inverse (x ++ y) = word_inverse y ++ word_inverse x.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
word_inverse (x ++ y) = word_inverse y ++ word_inverse x
  Proof.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
word_inverse (x ++ y) = word_inverse y ++ word_inverse x
    induction x as [|x xs].
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
y: Words
word_inverse (nil ++ y) = word_inverse y ++ word_inverse nil
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: H + K
xs: list (H + K)
y: Words
IHxs: word_inverse (xs ++ y) = word_inverse y ++ word_inverse xs
word_inverse ((x :: xs) ++ y) = word_inverse y ++ word_inverse (x :: xs)
    1: symmetry; apply app_nil.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: H + K
xs: list (H + K)
y: Words
IHxs: word_inverse (xs ++ y) = word_inverse y ++ word_inverse xs
word_inverse ((x :: xs) ++ y) = word_inverse y ++ word_inverse (x :: xs)
    simpl.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: H + K
xs: list (H + K)
y: Words
IHxs: word_inverse (xs ++ y) = word_inverse y ++ word_inverse xs
match x with
| inl g0 => word_inverse (xs ++ y) ++ [inl g0^]
| inr g0 => word_inverse (xs ++ y) ++ [inr g0^]
end =
word_inverse y ++
match x with
| inl g0 => word_inverse xs ++ [inl g0^]
| inr g0 => word_inverse xs ++ [inr g0^]
end
    destruct x; rhs napply app_assoc; f_ap.
  Defined.

  (** There are five source types for the path constructors. We will construct this HIT as the colimit of five forks going into [Words]. We can bundle up this colimit as a single coequalizer. *)

  (** Source types of path constructors *)
  Local Definition pc1 : Type := Words * H * H * Words.
  Local Definition pc2 : Type := Words * K * K * Words.
  Local Definition pc3 : Type := Words * G * Words.
  Local Definition pc4 : Type := Words * Words.
  Local Definition pc5 : Type := Words * Words.

  (** End points of the first path constructor *)
  Local Definition m1 : pc1 -> Words.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
pc1 -> Words
  Proof.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
pc1 -> Words
    intros [[[x h1] h2] y].
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: Words
h1, h2: H
y: Words
Words
    exact (x ++ (inl h1 :: [inl h2]) ++ y).
  Defined.

  Local Definition m1' : pc1 -> Words.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
pc1 -> Words
  Proof.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
pc1 -> Words
    intros [[[x h1] h2] y].
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: Words
h1, h2: H
y: Words
Words
    exact (x ++ [inl (h1 * h2)] ++ y).
  Defined.

  (** End points of the second path construct *)
  Local Definition m2 : pc2 -> Words.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
pc2 -> Words
  Proof.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
pc2 -> Words
    intros [[[x k1] k2] y].
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: Words
k1, k2: K
y: Words
Words
    exact (x ++ (inr k1 :: [inr k2]) ++ y).
  Defined.

  Local Definition m2' : pc2 -> Words.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
pc2 -> Words
  Proof.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
pc2 -> Words
    intros [[[x k1] k2] y].
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: Words
k1, k2: K
y: Words
Words
    exact (x ++ [inr (k1 * k2)] ++ y).
  Defined.

  (** End points of the third path constructor *)
  Local Definition m3 : pc3 -> Words.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
pc3 -> Words
  Proof.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
pc3 -> Words
    intros [[x z] y].
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: Words
z: G
y: Words
Words
    exact (x ++ [inl (f z)] ++ y).
  Defined.

  Local Definition m3' : pc3 -> Words.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
pc3 -> Words
  Proof.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
pc3 -> Words
    intros [[x z] y].
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: Words
z: G
y: Words
Words
    exact (x ++ [inr (g z)] ++ y).
  Defined.

  (** End points of the fourth path constructor *)
  Local Definition m4 : pc4 -> Words.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
pc4 -> Words
  Proof.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
pc4 -> Words
    intros [x y].
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
Words
    exact (x ++ [inl mon_unit] ++ y).
  Defined.

  Local Definition m4' : pc4 -> Words.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
pc4 -> Words
  Proof.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
pc4 -> Words
    intros [x y].
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
Words
    exact (x ++ y).
  Defined.

  (** End points of the fifth path constructor *)
  Local Definition m5 : pc5 -> Words.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
pc5 -> Words
  Proof.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
pc5 -> Words
    intros [x y].
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
Words
    exact (x ++ [inr mon_unit] ++ y).
  Defined.

  Local Definition m5' : pc5 -> Words.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
pc5 -> Words
  Proof.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
pc5 -> Words
    intros [x y].
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
Words
    exact (x ++ y).
  Defined.

  (** We can then define maps going into words consisting of the corresponding endpoints of the path constructors. *)
  Local Definition map1 : pc1 + pc2 + pc3 + pc4 + pc5 -> Words.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
pc1 + pc2 + pc3 + pc4 + pc5 -> Words
  Proof.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
pc1 + pc2 + pc3 + pc4 + pc5 -> Words
    intros [[[[x|x]|x]|x]|x].
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: pc1
Words
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: pc2
Words
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: pc3
Words
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: pc4
Words
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: pc5
Words
    +
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: pc1
Words exact (m1 x).
    +
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: pc2
Words exact (m2 x).
    +
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: pc3
Words exact (m3 x).
    +
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: pc4
Words exact (m4 x).
    +
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: pc5
Words exact (m5 x).
  Defined.

  Local Definition map2 : pc1 + pc2 + pc3 + pc4 + pc5 -> Words.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
pc1 + pc2 + pc3 + pc4 + pc5 -> Words
  Proof.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
pc1 + pc2 + pc3 + pc4 + pc5 -> Words
    intros [[[[x|x]|x]|x]|x].
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: pc1
Words
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: pc2
Words
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: pc3
Words
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: pc4
Words
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: pc5
Words
    +
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: pc1
Words exact (m1' x).
    +
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: pc2
Words exact (m2' x).
    +
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: pc3
Words exact (m3' x).
    +
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: pc4
Words exact (m4' x).
    +
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: pc5
Words exact (m5' x).
  Defined.

  (** Finally we can define our type as the 0-truncation of the coequalizer of these maps *)
  Definition amal_type : Type := Tr 0 (Coeq map1 map2).

  (** We can define the constructors *)

  Definition amal_eta : Words -> amal_type := tr o coeq.

  Definition amal_mu_H (x y : Words) (h1 h2 : H)
    : amal_eta (x ++ [inl h1, inl h2] ++ y) = amal_eta (x ++ [inl (h1 * h2)] ++ y).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
h1, h2: H
amal_eta (x ++ [inl h1, inl h2] ++ y) = amal_eta (x ++ [inl (h1 * h2)] ++ y)
  Proof.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
h1, h2: H
amal_eta (x ++ [inl h1, inl h2] ++ y) = amal_eta (x ++ [inl (h1 * h2)] ++ y)
    unfold amal_eta.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
h1, h2: H
tr (coeq (x ++ [inl h1, inl h2] ++ y)) =
tr (coeq (x ++ [inl (h1 * h2)] ++ y))
    apply path_Tr, tr.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
h1, h2: H
coeq (x ++ [inl h1, inl h2] ++ y) = coeq (x ++ [inl (h1 * h2)] ++ y)
    exact (cglue (inl (inl (inl (inl (x,h1,h2,y)))))).
  Defined.

  Definition amal_mu_K (x y : Words) (k1 k2 : K)
    : amal_eta (x ++ [inr k1, inr k2] ++ y) = amal_eta (x ++ [inr (k1 * k2)] ++ y).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
k1, k2: K
amal_eta (x ++ [inr k1, inr k2] ++ y) = amal_eta (x ++ [inr (k1 * k2)] ++ y)
  Proof.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
k1, k2: K
amal_eta (x ++ [inr k1, inr k2] ++ y) = amal_eta (x ++ [inr (k1 * k2)] ++ y)
    unfold amal_eta.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
k1, k2: K
tr (coeq (x ++ [inr k1, inr k2] ++ y)) =
tr (coeq (x ++ [inr (k1 * k2)] ++ y))
    apply path_Tr, tr.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
k1, k2: K
coeq (x ++ [inr k1, inr k2] ++ y) = coeq (x ++ [inr (k1 * k2)] ++ y)
    exact (cglue (inl (inl (inl (inr (x,k1,k2,y)))))).
  Defined.

  Definition amal_tau (x y : Words) (z : G)
    : amal_eta (x ++ [inl (f z)] ++ y) = amal_eta (x ++ [inr (g z)] ++ y).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
z: G
amal_eta (x ++ [inl (f z)] ++ y) = amal_eta (x ++ [inr (g z)] ++ y)
  Proof.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
z: G
amal_eta (x ++ [inl (f z)] ++ y) = amal_eta (x ++ [inr (g z)] ++ y)
    unfold amal_eta.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
z: G
tr (coeq (x ++ [inl (f z)] ++ y)) = tr (coeq (x ++ [inr (g z)] ++ y))
    apply path_Tr, tr.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
z: G
coeq (x ++ [inl (f z)] ++ y) = coeq (x ++ [inr (g z)] ++ y)
    exact (cglue (inl (inl (inr (x,z,y))))).
  Defined.

  Definition amal_omega_H (x y : Words)
    : amal_eta (x ++ [inl mon_unit] ++ y) = amal_eta (x ++ y).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
amal_eta (x ++ [inl 1] ++ y) = amal_eta (x ++ y)
  Proof.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
amal_eta (x ++ [inl 1] ++ y) = amal_eta (x ++ y)
    unfold amal_eta.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
tr (coeq (x ++ [inl 1] ++ y)) = tr (coeq (x ++ y))
    apply path_Tr, tr.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
coeq (x ++ [inl 1] ++ y) = coeq (x ++ y)
    exact (cglue (inl (inr (x,y)))).
  Defined.

  Definition amal_omega_K (x y : Words)
    : amal_eta (x ++ [inr mon_unit] ++ y) = amal_eta (x ++ y).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
amal_eta (x ++ [inr 1] ++ y) = amal_eta (x ++ y)
  Proof.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
amal_eta (x ++ [inr 1] ++ y) = amal_eta (x ++ y)
    unfold amal_eta.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
tr (coeq (x ++ [inr 1] ++ y)) = tr (coeq (x ++ y))
    apply path_Tr, tr.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
coeq (x ++ [inr 1] ++ y) = coeq (x ++ y)
    exact (cglue (inr (x,y))).
  Defined.

  (** Now we can derive the dependent eliminator *)

  Definition amal_type_ind (P : amal_type -> Type) `{forall x, IsHSet (P x)}
    (e : forall w, P (amal_eta w))
    (mh : forall (x y : Words) (h1 h2 : H),
      DPath P (amal_mu_H x y h1 h2) (e (x ++ [inl h1, inl h2] ++ y)) (e (x ++ [inl (h1 * h2)] ++ y)))
    (mk : forall (x y : Words) (k1 k2 : K),
      DPath P (amal_mu_K x y k1 k2) (e (x ++ [inr k1, inr k2] ++ y)) (e (x ++ [inr (k1 * k2)] ++ y)))
    (t : forall (x y : Words) (z : G),
      DPath P (amal_tau x y z) (e (x ++ [inl (f z)] ++ y)) (e (x ++ [inr (g z)] ++ y)))
    (oh : forall (x y : Words),
      DPath P (amal_omega_H x y) (e (x ++ [inl mon_unit] ++ y)) (e (x ++ y)))
    (ok : forall (x y : Words),
      DPath P (amal_omega_K x y) (e (x ++ [inr mon_unit] ++ y)) (e (x ++ y)))
    : forall x, P x.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x : amal_type, IsHSet (P x)
e: forall w : Words, P (amal_eta w)
mh: forall (x y : Words) (h1 h2 : H),
DPath P (amal_mu_H x y h1 h2) (e (x ++ [inl h1, inl h2] ++ y))
  (e (x ++ [inl (h1 * h2)] ++ y))
mk: forall (x y : Words) (k1 k2 : K),
DPath P (amal_mu_K x y k1 k2) (e (x ++ [inr k1, inr k2] ++ y))
  (e (x ++ [inr (k1 * k2)] ++ y))
t: forall (x y : Words) (z : G),
DPath P (amal_tau x y z) (e (x ++ [inl (f z)] ++ y))
  (e (x ++ [inr (g z)] ++ y))
oh: forall x y : Words,
DPath P (amal_omega_H x y) (e (x ++ [inl 1] ++ y)) (e (x ++ y))
ok: forall x y : Words,
DPath P (amal_omega_K x y) (e (x ++ [inr 1] ++ y)) (e (x ++ y))
forall x : amal_type, P x
  Proof.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x : amal_type, IsHSet (P x)
e: forall w : Words, P (amal_eta w)
mh: forall (x y : Words) (h1 h2 : H),
DPath P (amal_mu_H x y h1 h2) (e (x ++ [inl h1, inl h2] ++ y))
  (e (x ++ [inl (h1 * h2)] ++ y))
mk: forall (x y : Words) (k1 k2 : K),
DPath P (amal_mu_K x y k1 k2) (e (x ++ [inr k1, inr k2] ++ y))
  (e (x ++ [inr (k1 * k2)] ++ y))
t: forall (x y : Words) (z : G),
DPath P (amal_tau x y z) (e (x ++ [inl (f z)] ++ y))
  (e (x ++ [inr (g z)] ++ y))
oh: forall x y : Words,
DPath P (amal_omega_H x y) (e (x ++ [inl 1] ++ y)) (e (x ++ y))
ok: forall x y : Words,
DPath P (amal_omega_K x y) (e (x ++ [inr 1] ++ y)) (e (x ++ y))
forall x : amal_type, P x
    snapply Trunc_ind; [exact _|].
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x : amal_type, IsHSet (P x)
e: forall w : Words, P (amal_eta w)
mh: forall (x y : Words) (h1 h2 : H),
DPath P (amal_mu_H x y h1 h2) (e (x ++ [inl h1, inl h2] ++ y))
  (e (x ++ [inl (h1 * h2)] ++ y))
mk: forall (x y : Words) (k1 k2 : K),
DPath P (amal_mu_K x y k1 k2) (e (x ++ [inr k1, inr k2] ++ y))
  (e (x ++ [inr (k1 * k2)] ++ y))
t: forall (x y : Words) (z : G),
DPath P (amal_tau x y z) (e (x ++ [inl (f z)] ++ y))
  (e (x ++ [inr (g z)] ++ y))
oh: forall x y : Words,
DPath P (amal_omega_H x y) (e (x ++ [inl 1] ++ y)) (e (x ++ y))
ok: forall x y : Words,
DPath P (amal_omega_K x y) (e (x ++ [inr 1] ++ y)) (e (x ++ y))
forall a : Coeq map1 map2, P (tr a)
    snapply Coeq_ind.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x : amal_type, IsHSet (P x)
e: forall w : Words, P (amal_eta w)
mh: forall (x y : Words) (h1 h2 : H),
DPath P (amal_mu_H x y h1 h2) (e (x ++ [inl h1, inl h2] ++ y))
  (e (x ++ [inl (h1 * h2)] ++ y))
mk: forall (x y : Words) (k1 k2 : K),
DPath P (amal_mu_K x y k1 k2) (e (x ++ [inr k1, inr k2] ++ y))
  (e (x ++ [inr (k1 * k2)] ++ y))
t: forall (x y : Words) (z : G),
DPath P (amal_tau x y z) (e (x ++ [inl (f z)] ++ y))
  (e (x ++ [inr (g z)] ++ y))
oh: forall x y : Words,
DPath P (amal_omega_H x y) (e (x ++ [inl 1] ++ y)) (e (x ++ y))
ok: forall x y : Words,
DPath P (amal_omega_K x y) (e (x ++ [inr 1] ++ y)) (e (x ++ y))
forall a : Words, (fun w : Coeq map1 map2 => P (tr w)) (coeq a)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x : amal_type, IsHSet (P x)
e: forall w : Words, P (amal_eta w)
mh: forall (x y : Words) (h1 h2 : H),
DPath P (amal_mu_H x y h1 h2) (e (x ++ [inl h1, inl h2] ++ y))
  (e (x ++ [inl (h1 * h2)] ++ y))
mk: forall (x y : Words) (k1 k2 : K),
DPath P (amal_mu_K x y k1 k2) (e (x ++ [inr k1, inr k2] ++ y))
  (e (x ++ [inr (k1 * k2)] ++ y))
t: forall (x y : Words) (z : G),
DPath P (amal_tau x y z) (e (x ++ [inl (f z)] ++ y))
  (e (x ++ [inr (g z)] ++ y))
oh: forall x y : Words,
DPath P (amal_omega_H x y) (e (x ++ [inl 1] ++ y)) (e (x ++ y))
ok: forall x y : Words,
DPath P (amal_omega_K x y) (e (x ++ [inr 1] ++ y)) (e (x ++ y))
forall b : pc1 + pc2 + pc3 + pc4 + pc5,
transport (fun w : Coeq map1 map2 => P (tr w)) (cglue b) (?coeq' (map1 b)) =
?coeq' (map2 b)
    1: exact e.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x : amal_type, IsHSet (P x)
e: forall w : Words, P (amal_eta w)
mh: forall (x y : Words) (h1 h2 : H),
DPath P (amal_mu_H x y h1 h2) (e (x ++ [inl h1, inl h2] ++ y))
  (e (x ++ [inl (h1 * h2)] ++ y))
mk: forall (x y : Words) (k1 k2 : K),
DPath P (amal_mu_K x y k1 k2) (e (x ++ [inr k1, inr k2] ++ y))
  (e (x ++ [inr (k1 * k2)] ++ y))
t: forall (x y : Words) (z : G),
DPath P (amal_tau x y z) (e (x ++ [inl (f z)] ++ y))
  (e (x ++ [inr (g z)] ++ y))
oh: forall x y : Words,
DPath P (amal_omega_H x y) (e (x ++ [inl 1] ++ y)) (e (x ++ y))
ok: forall x y : Words,
DPath P (amal_omega_K x y) (e (x ++ [inr 1] ++ y)) (e (x ++ y))
forall b : pc1 + pc2 + pc3 + pc4 + pc5,
transport (fun w : Coeq map1 map2 => P (tr w)) (cglue b) (e (map1 b)) =
e (map2 b)
    intro a.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x : amal_type, IsHSet (P x)
e: forall w : Words, P (amal_eta w)
mh: forall (x y : Words) (h1 h2 : H),
DPath P (amal_mu_H x y h1 h2) (e (x ++ [inl h1, inl h2] ++ y))
  (e (x ++ [inl (h1 * h2)] ++ y))
mk: forall (x y : Words) (k1 k2 : K),
DPath P (amal_mu_K x y k1 k2) (e (x ++ [inr k1, inr k2] ++ y))
  (e (x ++ [inr (k1 * k2)] ++ y))
t: forall (x y : Words) (z : G),
DPath P (amal_tau x y z) (e (x ++ [inl (f z)] ++ y))
  (e (x ++ [inr (g z)] ++ y))
oh: forall x y : Words,
DPath P (amal_omega_H x y) (e (x ++ [inl 1] ++ y)) (e (x ++ y))
ok: forall x y : Words,
DPath P (amal_omega_K x y) (e (x ++ [inr 1] ++ y)) (e (x ++ y))
a: pc1 + pc2 + pc3 + pc4 + pc5
transport (fun w : Coeq map1 map2 => P (tr w)) (cglue a) (e (map1 a)) =
e (map2 a)
    destruct a as [ [ [ [a | a ] | a] | a ] | a ].
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x : amal_type, IsHSet (P x)
e: forall w : Words, P (amal_eta w)
mh: forall (x y : Words) (h1 h2 : H),
DPath P (amal_mu_H x y h1 h2) (e (x ++ [inl h1, inl h2] ++ y))
  (e (x ++ [inl (h1 * h2)] ++ y))
mk: forall (x y : Words) (k1 k2 : K),
DPath P (amal_mu_K x y k1 k2) (e (x ++ [inr k1, inr k2] ++ y))
  (e (x ++ [inr (k1 * k2)] ++ y))
t: forall (x y : Words) (z : G),
DPath P (amal_tau x y z) (e (x ++ [inl (f z)] ++ y))
  (e (x ++ [inr (g z)] ++ y))
oh: forall x y : Words,
DPath P (amal_omega_H x y) (e (x ++ [inl 1] ++ y)) (e (x ++ y))
ok: forall x y : Words,
DPath P (amal_omega_K x y) (e (x ++ [inr 1] ++ y)) (e (x ++ y))
a: pc1
transport (fun w : Coeq map1 map2 => P (tr w))
  (cglue (inl (inl (inl (inl a))))) (e (map1 (inl (inl (inl (inl a)))))) =
e (map2 (inl (inl (inl (inl a)))))
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x : amal_type, IsHSet (P x)
e: forall w : Words, P (amal_eta w)
mh: forall (x y : Words) (h1 h2 : H),
DPath P (amal_mu_H x y h1 h2) (e (x ++ [inl h1, inl h2] ++ y))
  (e (x ++ [inl (h1 * h2)] ++ y))
mk: forall (x y : Words) (k1 k2 : K),
DPath P (amal_mu_K x y k1 k2) (e (x ++ [inr k1, inr k2] ++ y))
  (e (x ++ [inr (k1 * k2)] ++ y))
t: forall (x y : Words) (z : G),
DPath P (amal_tau x y z) (e (x ++ [inl (f z)] ++ y))
  (e (x ++ [inr (g z)] ++ y))
oh: forall x y : Words,
DPath P (amal_omega_H x y) (e (x ++ [inl 1] ++ y)) (e (x ++ y))
ok: forall x y : Words,
DPath P (amal_omega_K x y) (e (x ++ [inr 1] ++ y)) (e (x ++ y))
a: pc2
transport (fun w : Coeq map1 map2 => P (tr w))
  (cglue (inl (inl (inl (inr a))))) (e (map1 (inl (inl (inl (inr a)))))) =
e (map2 (inl (inl (inl (inr a)))))
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x : amal_type, IsHSet (P x)
e: forall w : Words, P (amal_eta w)
mh: forall (x y : Words) (h1 h2 : H),
DPath P (amal_mu_H x y h1 h2) (e (x ++ [inl h1, inl h2] ++ y))
  (e (x ++ [inl (h1 * h2)] ++ y))
mk: forall (x y : Words) (k1 k2 : K),
DPath P (amal_mu_K x y k1 k2) (e (x ++ [inr k1, inr k2] ++ y))
  (e (x ++ [inr (k1 * k2)] ++ y))
t: forall (x y : Words) (z : G),
DPath P (amal_tau x y z) (e (x ++ [inl (f z)] ++ y))
  (e (x ++ [inr (g z)] ++ y))
oh: forall x y : Words,
DPath P (amal_omega_H x y) (e (x ++ [inl 1] ++ y)) (e (x ++ y))
ok: forall x y : Words,
DPath P (amal_omega_K x y) (e (x ++ [inr 1] ++ y)) (e (x ++ y))
a: pc3
transport (fun w : Coeq map1 map2 => P (tr w)) (cglue (inl (inl (inr a))))
  (e (map1 (inl (inl (inr a))))) =
e (map2 (inl (inl (inr a))))
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x : amal_type, IsHSet (P x)
e: forall w : Words, P (amal_eta w)
mh: forall (x y : Words) (h1 h2 : H),
DPath P (amal_mu_H x y h1 h2) (e (x ++ [inl h1, inl h2] ++ y))
  (e (x ++ [inl (h1 * h2)] ++ y))
mk: forall (x y : Words) (k1 k2 : K),
DPath P (amal_mu_K x y k1 k2) (e (x ++ [inr k1, inr k2] ++ y))
  (e (x ++ [inr (k1 * k2)] ++ y))
t: forall (x y : Words) (z : G),
DPath P (amal_tau x y z) (e (x ++ [inl (f z)] ++ y))
  (e (x ++ [inr (g z)] ++ y))
oh: forall x y : Words,
DPath P (amal_omega_H x y) (e (x ++ [inl 1] ++ y)) (e (x ++ y))
ok: forall x y : Words,
DPath P (amal_omega_K x y) (e (x ++ [inr 1] ++ y)) (e (x ++ y))
a: pc4
transport (fun w : Coeq map1 map2 => P (tr w)) (cglue (inl (inr a)))
  (e (map1 (inl (inr a)))) =
e (map2 (inl (inr a)))
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x : amal_type, IsHSet (P x)
e: forall w : Words, P (amal_eta w)
mh: forall (x y : Words) (h1 h2 : H),
DPath P (amal_mu_H x y h1 h2) (e (x ++ [inl h1, inl h2] ++ y))
  (e (x ++ [inl (h1 * h2)] ++ y))
mk: forall (x y : Words) (k1 k2 : K),
DPath P (amal_mu_K x y k1 k2) (e (x ++ [inr k1, inr k2] ++ y))
  (e (x ++ [inr (k1 * k2)] ++ y))
t: forall (x y : Words) (z : G),
DPath P (amal_tau x y z) (e (x ++ [inl (f z)] ++ y))
  (e (x ++ [inr (g z)] ++ y))
oh: forall x y : Words,
DPath P (amal_omega_H x y) (e (x ++ [inl 1] ++ y)) (e (x ++ y))
ok: forall x y : Words,
DPath P (amal_omega_K x y) (e (x ++ [inr 1] ++ y)) (e (x ++ y))
a: pc5
transport (fun w : Coeq map1 map2 => P (tr w)) (cglue (inr a))
  (e (map1 (inr a))) =
e (map2 (inr a))
    +
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x : amal_type, IsHSet (P x)
e: forall w : Words, P (amal_eta w)
mh: forall (x y : Words) (h1 h2 : H),
DPath P (amal_mu_H x y h1 h2) (e (x ++ [inl h1, inl h2] ++ y))
  (e (x ++ [inl (h1 * h2)] ++ y))
mk: forall (x y : Words) (k1 k2 : K),
DPath P (amal_mu_K x y k1 k2) (e (x ++ [inr k1, inr k2] ++ y))
  (e (x ++ [inr (k1 * k2)] ++ y))
t: forall (x y : Words) (z : G),
DPath P (amal_tau x y z) (e (x ++ [inl (f z)] ++ y))
  (e (x ++ [inr (g z)] ++ y))
oh: forall x y : Words,
DPath P (amal_omega_H x y) (e (x ++ [inl 1] ++ y)) (e (x ++ y))
ok: forall x y : Words,
DPath P (amal_omega_K x y) (e (x ++ [inr 1] ++ y)) (e (x ++ y))
a: pc1
transport (fun w : Coeq map1 map2 => P (tr w))
  (cglue (inl (inl (inl (inl a))))) (e (map1 (inl (inl (inl (inl a)))))) =
e (map2 (inl (inl (inl (inl a))))) destruct a as [[[x h1] h2] y].
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x0 : amal_type, IsHSet (P x0)
e: forall w : Words, P (amal_eta w)
mh: forall (x0 y0 : Words) (h0 h3 : H),
DPath P (amal_mu_H x0 y0 h0 h3) (e (x0 ++ [inl h0, inl h3] ++ y0))
  (e (x0 ++ [inl (h0 * h3)] ++ y0))
mk: forall (x0 y0 : Words) (k1 k2 : K),
DPath P (amal_mu_K x0 y0 k1 k2) (e (x0 ++ [inr k1, inr k2] ++ y0))
  (e (x0 ++ [inr (k1 * k2)] ++ y0))
t: forall (x0 y0 : Words) (z : G),
DPath P (amal_tau x0 y0 z) (e (x0 ++ [inl (f z)] ++ y0))
  (e (x0 ++ [inr (g z)] ++ y0))
oh: forall x0 y0 : Words,
DPath P (amal_omega_H x0 y0) (e (x0 ++ [inl 1] ++ y0)) (e (x0 ++ y0))
ok: forall x0 y0 : Words,
DPath P (amal_omega_K x0 y0) (e (x0 ++ [inr 1] ++ y0)) (e (x0 ++ y0))
x: Words
h1, h2: H
y: Words
transport (fun w : Coeq map1 map2 => P (tr w))
  (cglue (inl (inl (inl (inl (x, h1, h2, y))))))
  (e (map1 (inl (inl (inl (inl (x, h1, h2, y))))))) =
e (map2 (inl (inl (inl (inl (x, h1, h2, y))))))
      apply dp_compose.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x0 : amal_type, IsHSet (P x0)
e: forall w : Words, P (amal_eta w)
mh: forall (x0 y0 : Words) (h0 h3 : H),
DPath P (amal_mu_H x0 y0 h0 h3) (e (x0 ++ [inl h0, inl h3] ++ y0))
  (e (x0 ++ [inl (h0 * h3)] ++ y0))
mk: forall (x0 y0 : Words) (k1 k2 : K),
DPath P (amal_mu_K x0 y0 k1 k2) (e (x0 ++ [inr k1, inr k2] ++ y0))
  (e (x0 ++ [inr (k1 * k2)] ++ y0))
t: forall (x0 y0 : Words) (z : G),
DPath P (amal_tau x0 y0 z) (e (x0 ++ [inl (f z)] ++ y0))
  (e (x0 ++ [inr (g z)] ++ y0))
oh: forall x0 y0 : Words,
DPath P (amal_omega_H x0 y0) (e (x0 ++ [inl 1] ++ y0)) (e (x0 ++ y0))
ok: forall x0 y0 : Words,
DPath P (amal_omega_K x0 y0) (e (x0 ++ [inr 1] ++ y0)) (e (x0 ++ y0))
x: Words
h1, h2: H
y: Words
DPath P (ap tr (cglue (inl (inl (inl (inl (x, h1, h2, y)))))))
  (e (map1 (inl (inl (inl (inl (x, h1, h2, y)))))))
  (e (map2 (inl (inl (inl (inl (x, h1, h2, y)))))))
      exact (mh x y h1 h2).
    +
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x : amal_type, IsHSet (P x)
e: forall w : Words, P (amal_eta w)
mh: forall (x y : Words) (h1 h2 : H),
DPath P (amal_mu_H x y h1 h2) (e (x ++ [inl h1, inl h2] ++ y))
  (e (x ++ [inl (h1 * h2)] ++ y))
mk: forall (x y : Words) (k1 k2 : K),
DPath P (amal_mu_K x y k1 k2) (e (x ++ [inr k1, inr k2] ++ y))
  (e (x ++ [inr (k1 * k2)] ++ y))
t: forall (x y : Words) (z : G),
DPath P (amal_tau x y z) (e (x ++ [inl (f z)] ++ y))
  (e (x ++ [inr (g z)] ++ y))
oh: forall x y : Words,
DPath P (amal_omega_H x y) (e (x ++ [inl 1] ++ y)) (e (x ++ y))
ok: forall x y : Words,
DPath P (amal_omega_K x y) (e (x ++ [inr 1] ++ y)) (e (x ++ y))
a: pc2
transport (fun w : Coeq map1 map2 => P (tr w))
  (cglue (inl (inl (inl (inr a))))) (e (map1 (inl (inl (inl (inr a)))))) =
e (map2 (inl (inl (inl (inr a))))) destruct a as [[[x k1] k2] y].
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x0 : amal_type, IsHSet (P x0)
e: forall w : Words, P (amal_eta w)
mh: forall (x0 y0 : Words) (h1 h2 : H),
DPath P (amal_mu_H x0 y0 h1 h2) (e (x0 ++ [inl h1, inl h2] ++ y0))
  (e (x0 ++ [inl (h1 * h2)] ++ y0))
mk: forall (x0 y0 : Words) (k0 k3 : K),
DPath P (amal_mu_K x0 y0 k0 k3) (e (x0 ++ [inr k0, inr k3] ++ y0))
  (e (x0 ++ [inr (k0 * k3)] ++ y0))
t: forall (x0 y0 : Words) (z : G),
DPath P (amal_tau x0 y0 z) (e (x0 ++ [inl (f z)] ++ y0))
  (e (x0 ++ [inr (g z)] ++ y0))
oh: forall x0 y0 : Words,
DPath P (amal_omega_H x0 y0) (e (x0 ++ [inl 1] ++ y0)) (e (x0 ++ y0))
ok: forall x0 y0 : Words,
DPath P (amal_omega_K x0 y0) (e (x0 ++ [inr 1] ++ y0)) (e (x0 ++ y0))
x: Words
k1, k2: K
y: Words
transport (fun w : Coeq map1 map2 => P (tr w))
  (cglue (inl (inl (inl (inr (x, k1, k2, y))))))
  (e (map1 (inl (inl (inl (inr (x, k1, k2, y))))))) =
e (map2 (inl (inl (inl (inr (x, k1, k2, y))))))
      apply dp_compose.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x0 : amal_type, IsHSet (P x0)
e: forall w : Words, P (amal_eta w)
mh: forall (x0 y0 : Words) (h1 h2 : H),
DPath P (amal_mu_H x0 y0 h1 h2) (e (x0 ++ [inl h1, inl h2] ++ y0))
  (e (x0 ++ [inl (h1 * h2)] ++ y0))
mk: forall (x0 y0 : Words) (k0 k3 : K),
DPath P (amal_mu_K x0 y0 k0 k3) (e (x0 ++ [inr k0, inr k3] ++ y0))
  (e (x0 ++ [inr (k0 * k3)] ++ y0))
t: forall (x0 y0 : Words) (z : G),
DPath P (amal_tau x0 y0 z) (e (x0 ++ [inl (f z)] ++ y0))
  (e (x0 ++ [inr (g z)] ++ y0))
oh: forall x0 y0 : Words,
DPath P (amal_omega_H x0 y0) (e (x0 ++ [inl 1] ++ y0)) (e (x0 ++ y0))
ok: forall x0 y0 : Words,
DPath P (amal_omega_K x0 y0) (e (x0 ++ [inr 1] ++ y0)) (e (x0 ++ y0))
x: Words
k1, k2: K
y: Words
DPath P (ap tr (cglue (inl (inl (inl (inr (x, k1, k2, y)))))))
  (e (map1 (inl (inl (inl (inr (x, k1, k2, y)))))))
  (e (map2 (inl (inl (inl (inr (x, k1, k2, y)))))))
      exact (mk x y k1 k2).
    +
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x : amal_type, IsHSet (P x)
e: forall w : Words, P (amal_eta w)
mh: forall (x y : Words) (h1 h2 : H),
DPath P (amal_mu_H x y h1 h2) (e (x ++ [inl h1, inl h2] ++ y))
  (e (x ++ [inl (h1 * h2)] ++ y))
mk: forall (x y : Words) (k1 k2 : K),
DPath P (amal_mu_K x y k1 k2) (e (x ++ [inr k1, inr k2] ++ y))
  (e (x ++ [inr (k1 * k2)] ++ y))
t: forall (x y : Words) (z : G),
DPath P (amal_tau x y z) (e (x ++ [inl (f z)] ++ y))
  (e (x ++ [inr (g z)] ++ y))
oh: forall x y : Words,
DPath P (amal_omega_H x y) (e (x ++ [inl 1] ++ y)) (e (x ++ y))
ok: forall x y : Words,
DPath P (amal_omega_K x y) (e (x ++ [inr 1] ++ y)) (e (x ++ y))
a: pc3
transport (fun w : Coeq map1 map2 => P (tr w)) (cglue (inl (inl (inr a))))
  (e (map1 (inl (inl (inr a))))) =
e (map2 (inl (inl (inr a)))) destruct a as [[x z] y].
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x0 : amal_type, IsHSet (P x0)
e: forall w : Words, P (amal_eta w)
mh: forall (x0 y0 : Words) (h1 h2 : H),
DPath P (amal_mu_H x0 y0 h1 h2) (e (x0 ++ [inl h1, inl h2] ++ y0))
  (e (x0 ++ [inl (h1 * h2)] ++ y0))
mk: forall (x0 y0 : Words) (k1 k2 : K),
DPath P (amal_mu_K x0 y0 k1 k2) (e (x0 ++ [inr k1, inr k2] ++ y0))
  (e (x0 ++ [inr (k1 * k2)] ++ y0))
t: forall (x0 y0 : Words) (z0 : G),
DPath P (amal_tau x0 y0 z0) (e (x0 ++ [inl (f z0)] ++ y0))
  (e (x0 ++ [inr (g z0)] ++ y0))
oh: forall x0 y0 : Words,
DPath P (amal_omega_H x0 y0) (e (x0 ++ [inl 1] ++ y0)) (e (x0 ++ y0))
ok: forall x0 y0 : Words,
DPath P (amal_omega_K x0 y0) (e (x0 ++ [inr 1] ++ y0)) (e (x0 ++ y0))
x: Words
z: G
y: Words
transport (fun w : Coeq map1 map2 => P (tr w))
  (cglue (inl (inl (inr (x, z, y))))) (e (map1 (inl (inl (inr (x, z, y)))))) =
e (map2 (inl (inl (inr (x, z, y)))))
      apply dp_compose.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x0 : amal_type, IsHSet (P x0)
e: forall w : Words, P (amal_eta w)
mh: forall (x0 y0 : Words) (h1 h2 : H),
DPath P (amal_mu_H x0 y0 h1 h2) (e (x0 ++ [inl h1, inl h2] ++ y0))
  (e (x0 ++ [inl (h1 * h2)] ++ y0))
mk: forall (x0 y0 : Words) (k1 k2 : K),
DPath P (amal_mu_K x0 y0 k1 k2) (e (x0 ++ [inr k1, inr k2] ++ y0))
  (e (x0 ++ [inr (k1 * k2)] ++ y0))
t: forall (x0 y0 : Words) (z0 : G),
DPath P (amal_tau x0 y0 z0) (e (x0 ++ [inl (f z0)] ++ y0))
  (e (x0 ++ [inr (g z0)] ++ y0))
oh: forall x0 y0 : Words,
DPath P (amal_omega_H x0 y0) (e (x0 ++ [inl 1] ++ y0)) (e (x0 ++ y0))
ok: forall x0 y0 : Words,
DPath P (amal_omega_K x0 y0) (e (x0 ++ [inr 1] ++ y0)) (e (x0 ++ y0))
x: Words
z: G
y: Words
DPath P (ap tr (cglue (inl (inl (inr (x, z, y))))))
  (e (map1 (inl (inl (inr (x, z, y))))))
  (e (map2 (inl (inl (inr (x, z, y))))))
      exact (t x y z).
    +
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x : amal_type, IsHSet (P x)
e: forall w : Words, P (amal_eta w)
mh: forall (x y : Words) (h1 h2 : H),
DPath P (amal_mu_H x y h1 h2) (e (x ++ [inl h1, inl h2] ++ y))
  (e (x ++ [inl (h1 * h2)] ++ y))
mk: forall (x y : Words) (k1 k2 : K),
DPath P (amal_mu_K x y k1 k2) (e (x ++ [inr k1, inr k2] ++ y))
  (e (x ++ [inr (k1 * k2)] ++ y))
t: forall (x y : Words) (z : G),
DPath P (amal_tau x y z) (e (x ++ [inl (f z)] ++ y))
  (e (x ++ [inr (g z)] ++ y))
oh: forall x y : Words,
DPath P (amal_omega_H x y) (e (x ++ [inl 1] ++ y)) (e (x ++ y))
ok: forall x y : Words,
DPath P (amal_omega_K x y) (e (x ++ [inr 1] ++ y)) (e (x ++ y))
a: pc4
transport (fun w : Coeq map1 map2 => P (tr w)) (cglue (inl (inr a)))
  (e (map1 (inl (inr a)))) =
e (map2 (inl (inr a))) destruct a as [x y].
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x0 : amal_type, IsHSet (P x0)
e: forall w : Words, P (amal_eta w)
mh: forall (x0 y0 : Words) (h1 h2 : H),
DPath P (amal_mu_H x0 y0 h1 h2) (e (x0 ++ [inl h1, inl h2] ++ y0))
  (e (x0 ++ [inl (h1 * h2)] ++ y0))
mk: forall (x0 y0 : Words) (k1 k2 : K),
DPath P (amal_mu_K x0 y0 k1 k2) (e (x0 ++ [inr k1, inr k2] ++ y0))
  (e (x0 ++ [inr (k1 * k2)] ++ y0))
t: forall (x0 y0 : Words) (z : G),
DPath P (amal_tau x0 y0 z) (e (x0 ++ [inl (f z)] ++ y0))
  (e (x0 ++ [inr (g z)] ++ y0))
oh: forall x0 y0 : Words,
DPath P (amal_omega_H x0 y0) (e (x0 ++ [inl 1] ++ y0)) (e (x0 ++ y0))
ok: forall x0 y0 : Words,
DPath P (amal_omega_K x0 y0) (e (x0 ++ [inr 1] ++ y0)) (e (x0 ++ y0))
x, y: Words
transport (fun w : Coeq map1 map2 => P (tr w)) (cglue (inl (inr (x, y))))
  (e (map1 (inl (inr (x, y))))) =
e (map2 (inl (inr (x, y))))
      apply dp_compose.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x0 : amal_type, IsHSet (P x0)
e: forall w : Words, P (amal_eta w)
mh: forall (x0 y0 : Words) (h1 h2 : H),
DPath P (amal_mu_H x0 y0 h1 h2) (e (x0 ++ [inl h1, inl h2] ++ y0))
  (e (x0 ++ [inl (h1 * h2)] ++ y0))
mk: forall (x0 y0 : Words) (k1 k2 : K),
DPath P (amal_mu_K x0 y0 k1 k2) (e (x0 ++ [inr k1, inr k2] ++ y0))
  (e (x0 ++ [inr (k1 * k2)] ++ y0))
t: forall (x0 y0 : Words) (z : G),
DPath P (amal_tau x0 y0 z) (e (x0 ++ [inl (f z)] ++ y0))
  (e (x0 ++ [inr (g z)] ++ y0))
oh: forall x0 y0 : Words,
DPath P (amal_omega_H x0 y0) (e (x0 ++ [inl 1] ++ y0)) (e (x0 ++ y0))
ok: forall x0 y0 : Words,
DPath P (amal_omega_K x0 y0) (e (x0 ++ [inr 1] ++ y0)) (e (x0 ++ y0))
x, y: Words
DPath P (ap tr (cglue (inl (inr (x, y))))) (e (map1 (inl (inr (x, y)))))
  (e (map2 (inl (inr (x, y)))))
      exact (oh x y).
    +
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x : amal_type, IsHSet (P x)
e: forall w : Words, P (amal_eta w)
mh: forall (x y : Words) (h1 h2 : H),
DPath P (amal_mu_H x y h1 h2) (e (x ++ [inl h1, inl h2] ++ y))
  (e (x ++ [inl (h1 * h2)] ++ y))
mk: forall (x y : Words) (k1 k2 : K),
DPath P (amal_mu_K x y k1 k2) (e (x ++ [inr k1, inr k2] ++ y))
  (e (x ++ [inr (k1 * k2)] ++ y))
t: forall (x y : Words) (z : G),
DPath P (amal_tau x y z) (e (x ++ [inl (f z)] ++ y))
  (e (x ++ [inr (g z)] ++ y))
oh: forall x y : Words,
DPath P (amal_omega_H x y) (e (x ++ [inl 1] ++ y)) (e (x ++ y))
ok: forall x y : Words,
DPath P (amal_omega_K x y) (e (x ++ [inr 1] ++ y)) (e (x ++ y))
a: pc5
transport (fun w : Coeq map1 map2 => P (tr w)) (cglue (inr a))
  (e (map1 (inr a))) =
e (map2 (inr a)) destruct a as [x y].
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x0 : amal_type, IsHSet (P x0)
e: forall w : Words, P (amal_eta w)
mh: forall (x0 y0 : Words) (h1 h2 : H),
DPath P (amal_mu_H x0 y0 h1 h2) (e (x0 ++ [inl h1, inl h2] ++ y0))
  (e (x0 ++ [inl (h1 * h2)] ++ y0))
mk: forall (x0 y0 : Words) (k1 k2 : K),
DPath P (amal_mu_K x0 y0 k1 k2) (e (x0 ++ [inr k1, inr k2] ++ y0))
  (e (x0 ++ [inr (k1 * k2)] ++ y0))
t: forall (x0 y0 : Words) (z : G),
DPath P (amal_tau x0 y0 z) (e (x0 ++ [inl (f z)] ++ y0))
  (e (x0 ++ [inr (g z)] ++ y0))
oh: forall x0 y0 : Words,
DPath P (amal_omega_H x0 y0) (e (x0 ++ [inl 1] ++ y0)) (e (x0 ++ y0))
ok: forall x0 y0 : Words,
DPath P (amal_omega_K x0 y0) (e (x0 ++ [inr 1] ++ y0)) (e (x0 ++ y0))
x, y: Words
transport (fun w : Coeq map1 map2 => P (tr w)) (cglue (inr (x, y)))
  (e (map1 (inr (x, y)))) =
e (map2 (inr (x, y)))
      apply dp_compose.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x0 : amal_type, IsHSet (P x0)
e: forall w : Words, P (amal_eta w)
mh: forall (x0 y0 : Words) (h1 h2 : H),
DPath P (amal_mu_H x0 y0 h1 h2) (e (x0 ++ [inl h1, inl h2] ++ y0))
  (e (x0 ++ [inl (h1 * h2)] ++ y0))
mk: forall (x0 y0 : Words) (k1 k2 : K),
DPath P (amal_mu_K x0 y0 k1 k2) (e (x0 ++ [inr k1, inr k2] ++ y0))
  (e (x0 ++ [inr (k1 * k2)] ++ y0))
t: forall (x0 y0 : Words) (z : G),
DPath P (amal_tau x0 y0 z) (e (x0 ++ [inl (f z)] ++ y0))
  (e (x0 ++ [inr (g z)] ++ y0))
oh: forall x0 y0 : Words,
DPath P (amal_omega_H x0 y0) (e (x0 ++ [inl 1] ++ y0)) (e (x0 ++ y0))
ok: forall x0 y0 : Words,
DPath P (amal_omega_K x0 y0) (e (x0 ++ [inr 1] ++ y0)) (e (x0 ++ y0))
x, y: Words
DPath P (ap tr (cglue (inr (x, y)))) (e (map1 (inr (x, y))))
  (e (map2 (inr (x, y))))
      exact (ok x y).
  Defined.

  Definition amal_type_ind_hprop (P : amal_type -> Type) `{forall x, IsHProp (P x)}
    (e : forall w, P (amal_eta w))
    : forall x, P x.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x : amal_type, IsHProp (P x)
e: forall w : Words, P (amal_eta w)
forall x : amal_type, P x
  Proof.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x : amal_type, IsHProp (P x)
e: forall w : Words, P (amal_eta w)
forall x : amal_type, P x
    snapply amal_type_ind.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x : amal_type, IsHProp (P x)
e: forall w : Words, P (amal_eta w)
forall x : amal_type, IsHSet (P x)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x : amal_type, IsHProp (P x)
e: forall w : Words, P (amal_eta w)
forall w : Words, P (amal_eta w)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x : amal_type, IsHProp (P x)
e: forall w : Words, P (amal_eta w)
forall (x y : Words) (h1 h2 : H),
DPath P (amal_mu_H x y h1 h2) (?e (x ++ [inl h1, inl h2] ++ y))
  (?e (x ++ [inl (h1 * h2)] ++ y))
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x : amal_type, IsHProp (P x)
e: forall w : Words, P (amal_eta w)
forall (x y : Words) (k1 k2 : K),
DPath P (amal_mu_K x y k1 k2) (?e (x ++ [inr k1, inr k2] ++ y))
  (?e (x ++ [inr (k1 * k2)] ++ y))
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x : amal_type, IsHProp (P x)
e: forall w : Words, P (amal_eta w)
forall (x y : Words) (z : G),
DPath P (amal_tau x y z) (?e (x ++ [inl (f z)] ++ y))
  (?e (x ++ [inr (g z)] ++ y))
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x : amal_type, IsHProp (P x)
e: forall w : Words, P (amal_eta w)
forall x y : Words,
DPath P (amal_omega_H x y) (?e (x ++ [inl 1] ++ y)) (?e (x ++ y))
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x : amal_type, IsHProp (P x)
e: forall w : Words, P (amal_eta w)
forall x y : Words,
DPath P (amal_omega_K x y) (?e (x ++ [inr 1] ++ y)) (?e (x ++ y))
    1: exact _.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x : amal_type, IsHProp (P x)
e: forall w : Words, P (amal_eta w)
forall w : Words, P (amal_eta w)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x : amal_type, IsHProp (P x)
e: forall w : Words, P (amal_eta w)
forall (x y : Words) (h1 h2 : H),
DPath P (amal_mu_H x y h1 h2) (?e (x ++ [inl h1, inl h2] ++ y))
  (?e (x ++ [inl (h1 * h2)] ++ y))
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x : amal_type, IsHProp (P x)
e: forall w : Words, P (amal_eta w)
forall (x y : Words) (k1 k2 : K),
DPath P (amal_mu_K x y k1 k2) (?e (x ++ [inr k1, inr k2] ++ y))
  (?e (x ++ [inr (k1 * k2)] ++ y))
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x : amal_type, IsHProp (P x)
e: forall w : Words, P (amal_eta w)
forall (x y : Words) (z : G),
DPath P (amal_tau x y z) (?e (x ++ [inl (f z)] ++ y))
  (?e (x ++ [inr (g z)] ++ y))
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x : amal_type, IsHProp (P x)
e: forall w : Words, P (amal_eta w)
forall x y : Words,
DPath P (amal_omega_H x y) (?e (x ++ [inl 1] ++ y)) (?e (x ++ y))
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x : amal_type, IsHProp (P x)
e: forall w : Words, P (amal_eta w)
forall x y : Words,
DPath P (amal_omega_K x y) (?e (x ++ [inr 1] ++ y)) (?e (x ++ y))
    1: exact e.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x : amal_type, IsHProp (P x)
e: forall w : Words, P (amal_eta w)
forall (x y : Words) (h1 h2 : H),
DPath P (amal_mu_H x y h1 h2) (e (x ++ [inl h1, inl h2] ++ y))
  (e (x ++ [inl (h1 * h2)] ++ y))
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x : amal_type, IsHProp (P x)
e: forall w : Words, P (amal_eta w)
forall (x y : Words) (k1 k2 : K),
DPath P (amal_mu_K x y k1 k2) (e (x ++ [inr k1, inr k2] ++ y))
  (e (x ++ [inr (k1 * k2)] ++ y))
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x : amal_type, IsHProp (P x)
e: forall w : Words, P (amal_eta w)
forall (x y : Words) (z : G),
DPath P (amal_tau x y z) (e (x ++ [inl (f z)] ++ y))
  (e (x ++ [inr (g z)] ++ y))
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x : amal_type, IsHProp (P x)
e: forall w : Words, P (amal_eta w)
forall x y : Words,
DPath P (amal_omega_H x y) (e (x ++ [inl 1] ++ y)) (e (x ++ y))
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: amal_type -> Type
H0: forall x : amal_type, IsHProp (P x)
e: forall w : Words, P (amal_eta w)
forall x y : Words,
DPath P (amal_omega_K x y) (e (x ++ [inr 1] ++ y)) (e (x ++ y))
    all: intros; apply path_ishprop.
  Defined.

  (** From which we can derive the non-dependent eliminator / recursion principle *)
  Definition amal_type_rec (P : Type) `{IsHSet P} (e : Words -> P)
    (eh : forall (x y : Words) (h1 h2 : H),
      e (x ++ [inl h1, inl h2] ++ y) = e (x ++ [inl (h1 * h2)] ++ y))
    (ek : forall (x y : Words) (k1 k2 : K),
      e (x ++ [inr k1, inr k2] ++ y) = e (x ++ [inr (k1 * k2)] ++ y))
    (t : forall (x y : Words) (z : G),
      e (x ++ [inl (f z)] ++ y) = e (x ++ [inr (g z)] ++ y))
    (oh : forall (x y : Words), e (x ++ [inl mon_unit] ++ y) = e (x ++ y))
    (ok : forall (x y : Words), e (x ++ [inr mon_unit] ++ y) = e (x ++ y))
    : amal_type -> P.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: Type
IsHSet0: IsHSet P
e: Words -> P
eh: forall (x y : Words) (h1 h2 : H),
e (x ++ [inl h1, inl h2] ++ y) = e (x ++ [inl (h1 * h2)] ++ y)
ek: forall (x y : Words) (k1 k2 : K),
e (x ++ [inr k1, inr k2] ++ y) = e (x ++ [inr (k1 * k2)] ++ y)
t: forall (x y : Words) (z : G),
e (x ++ [inl (f z)] ++ y) = e (x ++ [inr (g z)] ++ y)
oh: forall x y : Words, e (x ++ [inl 1] ++ y) = e (x ++ y)
ok: forall x y : Words, e (x ++ [inr 1] ++ y) = e (x ++ y)
amal_type -> P
  Proof.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: Type
IsHSet0: IsHSet P
e: Words -> P
eh: forall (x y : Words) (h1 h2 : H),
e (x ++ [inl h1, inl h2] ++ y) = e (x ++ [inl (h1 * h2)] ++ y)
ek: forall (x y : Words) (k1 k2 : K),
e (x ++ [inr k1, inr k2] ++ y) = e (x ++ [inr (k1 * k2)] ++ y)
t: forall (x y : Words) (z : G),
e (x ++ [inl (f z)] ++ y) = e (x ++ [inr (g z)] ++ y)
oh: forall x y : Words, e (x ++ [inl 1] ++ y) = e (x ++ y)
ok: forall x y : Words, e (x ++ [inr 1] ++ y) = e (x ++ y)
amal_type -> P
    snapply amal_type_ind.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: Type
IsHSet0: IsHSet P
e: Words -> P
eh: forall (x y : Words) (h1 h2 : H),
e (x ++ [inl h1, inl h2] ++ y) = e (x ++ [inl (h1 * h2)] ++ y)
ek: forall (x y : Words) (k1 k2 : K),
e (x ++ [inr k1, inr k2] ++ y) = e (x ++ [inr (k1 * k2)] ++ y)
t: forall (x y : Words) (z : G),
e (x ++ [inl (f z)] ++ y) = e (x ++ [inr (g z)] ++ y)
oh: forall x y : Words, e (x ++ [inl 1] ++ y) = e (x ++ y)
ok: forall x y : Words, e (x ++ [inr 1] ++ y) = e (x ++ y)
forall x : amal_type, IsHSet ((fun _ : amal_type => P) x)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: Type
IsHSet0: IsHSet P
e: Words -> P
eh: forall (x y : Words) (h1 h2 : H),
e (x ++ [inl h1, inl h2] ++ y) = e (x ++ [inl (h1 * h2)] ++ y)
ek: forall (x y : Words) (k1 k2 : K),
e (x ++ [inr k1, inr k2] ++ y) = e (x ++ [inr (k1 * k2)] ++ y)
t: forall (x y : Words) (z : G),
e (x ++ [inl (f z)] ++ y) = e (x ++ [inr (g z)] ++ y)
oh: forall x y : Words, e (x ++ [inl 1] ++ y) = e (x ++ y)
ok: forall x y : Words, e (x ++ [inr 1] ++ y) = e (x ++ y)
forall w : Words, (fun _ : amal_type => P) (amal_eta w)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: Type
IsHSet0: IsHSet P
e: Words -> P
eh: forall (x y : Words) (h1 h2 : H),
e (x ++ [inl h1, inl h2] ++ y) = e (x ++ [inl (h1 * h2)] ++ y)
ek: forall (x y : Words) (k1 k2 : K),
e (x ++ [inr k1, inr k2] ++ y) = e (x ++ [inr (k1 * k2)] ++ y)
t: forall (x y : Words) (z : G),
e (x ++ [inl (f z)] ++ y) = e (x ++ [inr (g z)] ++ y)
oh: forall x y : Words, e (x ++ [inl 1] ++ y) = e (x ++ y)
ok: forall x y : Words, e (x ++ [inr 1] ++ y) = e (x ++ y)
forall (x y : Words) (h1 h2 : H),
DPath (fun _ : amal_type => P) (amal_mu_H x y h1 h2)
  (?e (x ++ [inl h1, inl h2] ++ y)) (?e (x ++ [inl (h1 * h2)] ++ y))
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: Type
IsHSet0: IsHSet P
e: Words -> P
eh: forall (x y : Words) (h1 h2 : H),
e (x ++ [inl h1, inl h2] ++ y) = e (x ++ [inl (h1 * h2)] ++ y)
ek: forall (x y : Words) (k1 k2 : K),
e (x ++ [inr k1, inr k2] ++ y) = e (x ++ [inr (k1 * k2)] ++ y)
t: forall (x y : Words) (z : G),
e (x ++ [inl (f z)] ++ y) = e (x ++ [inr (g z)] ++ y)
oh: forall x y : Words, e (x ++ [inl 1] ++ y) = e (x ++ y)
ok: forall x y : Words, e (x ++ [inr 1] ++ y) = e (x ++ y)
forall (x y : Words) (k1 k2 : K),
DPath (fun _ : amal_type => P) (amal_mu_K x y k1 k2)
  (?e (x ++ [inr k1, inr k2] ++ y)) (?e (x ++ [inr (k1 * k2)] ++ y))
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: Type
IsHSet0: IsHSet P
e: Words -> P
eh: forall (x y : Words) (h1 h2 : H),
e (x ++ [inl h1, inl h2] ++ y) = e (x ++ [inl (h1 * h2)] ++ y)
ek: forall (x y : Words) (k1 k2 : K),
e (x ++ [inr k1, inr k2] ++ y) = e (x ++ [inr (k1 * k2)] ++ y)
t: forall (x y : Words) (z : G),
e (x ++ [inl (f z)] ++ y) = e (x ++ [inr (g z)] ++ y)
oh: forall x y : Words, e (x ++ [inl 1] ++ y) = e (x ++ y)
ok: forall x y : Words, e (x ++ [inr 1] ++ y) = e (x ++ y)
forall (x y : Words) (z : G),
DPath (fun _ : amal_type => P) (amal_tau x y z) (?e (x ++ [inl (f z)] ++ y))
  (?e (x ++ [inr (g z)] ++ y))
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: Type
IsHSet0: IsHSet P
e: Words -> P
eh: forall (x y : Words) (h1 h2 : H),
e (x ++ [inl h1, inl h2] ++ y) = e (x ++ [inl (h1 * h2)] ++ y)
ek: forall (x y : Words) (k1 k2 : K),
e (x ++ [inr k1, inr k2] ++ y) = e (x ++ [inr (k1 * k2)] ++ y)
t: forall (x y : Words) (z : G),
e (x ++ [inl (f z)] ++ y) = e (x ++ [inr (g z)] ++ y)
oh: forall x y : Words, e (x ++ [inl 1] ++ y) = e (x ++ y)
ok: forall x y : Words, e (x ++ [inr 1] ++ y) = e (x ++ y)
forall x y : Words,
DPath (fun _ : amal_type => P) (amal_omega_H x y) 
  (?e (x ++ [inl 1] ++ y)) (?e (x ++ y))
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: Type
IsHSet0: IsHSet P
e: Words -> P
eh: forall (x y : Words) (h1 h2 : H),
e (x ++ [inl h1, inl h2] ++ y) = e (x ++ [inl (h1 * h2)] ++ y)
ek: forall (x y : Words) (k1 k2 : K),
e (x ++ [inr k1, inr k2] ++ y) = e (x ++ [inr (k1 * k2)] ++ y)
t: forall (x y : Words) (z : G),
e (x ++ [inl (f z)] ++ y) = e (x ++ [inr (g z)] ++ y)
oh: forall x y : Words, e (x ++ [inl 1] ++ y) = e (x ++ y)
ok: forall x y : Words, e (x ++ [inr 1] ++ y) = e (x ++ y)
forall x y : Words,
DPath (fun _ : amal_type => P) (amal_omega_K x y) 
  (?e (x ++ [inr 1] ++ y)) (?e (x ++ y))
    1: exact _.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: Type
IsHSet0: IsHSet P
e: Words -> P
eh: forall (x y : Words) (h1 h2 : H),
e (x ++ [inl h1, inl h2] ++ y) = e (x ++ [inl (h1 * h2)] ++ y)
ek: forall (x y : Words) (k1 k2 : K),
e (x ++ [inr k1, inr k2] ++ y) = e (x ++ [inr (k1 * k2)] ++ y)
t: forall (x y : Words) (z : G),
e (x ++ [inl (f z)] ++ y) = e (x ++ [inr (g z)] ++ y)
oh: forall x y : Words, e (x ++ [inl 1] ++ y) = e (x ++ y)
ok: forall x y : Words, e (x ++ [inr 1] ++ y) = e (x ++ y)
forall w : Words, (fun _ : amal_type => P) (amal_eta w)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: Type
IsHSet0: IsHSet P
e: Words -> P
eh: forall (x y : Words) (h1 h2 : H),
e (x ++ [inl h1, inl h2] ++ y) = e (x ++ [inl (h1 * h2)] ++ y)
ek: forall (x y : Words) (k1 k2 : K),
e (x ++ [inr k1, inr k2] ++ y) = e (x ++ [inr (k1 * k2)] ++ y)
t: forall (x y : Words) (z : G),
e (x ++ [inl (f z)] ++ y) = e (x ++ [inr (g z)] ++ y)
oh: forall x y : Words, e (x ++ [inl 1] ++ y) = e (x ++ y)
ok: forall x y : Words, e (x ++ [inr 1] ++ y) = e (x ++ y)
forall (x y : Words) (h1 h2 : H),
DPath (fun _ : amal_type => P) (amal_mu_H x y h1 h2)
  (?e (x ++ [inl h1, inl h2] ++ y)) (?e (x ++ [inl (h1 * h2)] ++ y))
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: Type
IsHSet0: IsHSet P
e: Words -> P
eh: forall (x y : Words) (h1 h2 : H),
e (x ++ [inl h1, inl h2] ++ y) = e (x ++ [inl (h1 * h2)] ++ y)
ek: forall (x y : Words) (k1 k2 : K),
e (x ++ [inr k1, inr k2] ++ y) = e (x ++ [inr (k1 * k2)] ++ y)
t: forall (x y : Words) (z : G),
e (x ++ [inl (f z)] ++ y) = e (x ++ [inr (g z)] ++ y)
oh: forall x y : Words, e (x ++ [inl 1] ++ y) = e (x ++ y)
ok: forall x y : Words, e (x ++ [inr 1] ++ y) = e (x ++ y)
forall (x y : Words) (k1 k2 : K),
DPath (fun _ : amal_type => P) (amal_mu_K x y k1 k2)
  (?e (x ++ [inr k1, inr k2] ++ y)) (?e (x ++ [inr (k1 * k2)] ++ y))
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: Type
IsHSet0: IsHSet P
e: Words -> P
eh: forall (x y : Words) (h1 h2 : H),
e (x ++ [inl h1, inl h2] ++ y) = e (x ++ [inl (h1 * h2)] ++ y)
ek: forall (x y : Words) (k1 k2 : K),
e (x ++ [inr k1, inr k2] ++ y) = e (x ++ [inr (k1 * k2)] ++ y)
t: forall (x y : Words) (z : G),
e (x ++ [inl (f z)] ++ y) = e (x ++ [inr (g z)] ++ y)
oh: forall x y : Words, e (x ++ [inl 1] ++ y) = e (x ++ y)
ok: forall x y : Words, e (x ++ [inr 1] ++ y) = e (x ++ y)
forall (x y : Words) (z : G),
DPath (fun _ : amal_type => P) (amal_tau x y z) (?e (x ++ [inl (f z)] ++ y))
  (?e (x ++ [inr (g z)] ++ y))
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: Type
IsHSet0: IsHSet P
e: Words -> P
eh: forall (x y : Words) (h1 h2 : H),
e (x ++ [inl h1, inl h2] ++ y) = e (x ++ [inl (h1 * h2)] ++ y)
ek: forall (x y : Words) (k1 k2 : K),
e (x ++ [inr k1, inr k2] ++ y) = e (x ++ [inr (k1 * k2)] ++ y)
t: forall (x y : Words) (z : G),
e (x ++ [inl (f z)] ++ y) = e (x ++ [inr (g z)] ++ y)
oh: forall x y : Words, e (x ++ [inl 1] ++ y) = e (x ++ y)
ok: forall x y : Words, e (x ++ [inr 1] ++ y) = e (x ++ y)
forall x y : Words,
DPath (fun _ : amal_type => P) (amal_omega_H x y) 
  (?e (x ++ [inl 1] ++ y)) (?e (x ++ y))
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: Type
IsHSet0: IsHSet P
e: Words -> P
eh: forall (x y : Words) (h1 h2 : H),
e (x ++ [inl h1, inl h2] ++ y) = e (x ++ [inl (h1 * h2)] ++ y)
ek: forall (x y : Words) (k1 k2 : K),
e (x ++ [inr k1, inr k2] ++ y) = e (x ++ [inr (k1 * k2)] ++ y)
t: forall (x y : Words) (z : G),
e (x ++ [inl (f z)] ++ y) = e (x ++ [inr (g z)] ++ y)
oh: forall x y : Words, e (x ++ [inl 1] ++ y) = e (x ++ y)
ok: forall x y : Words, e (x ++ [inr 1] ++ y) = e (x ++ y)
forall x y : Words,
DPath (fun _ : amal_type => P) (amal_omega_K x y) 
  (?e (x ++ [inr 1] ++ y)) (?e (x ++ y))
    1: exact e.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: Type
IsHSet0: IsHSet P
e: Words -> P
eh: forall (x y : Words) (h1 h2 : H),
e (x ++ [inl h1, inl h2] ++ y) = e (x ++ [inl (h1 * h2)] ++ y)
ek: forall (x y : Words) (k1 k2 : K),
e (x ++ [inr k1, inr k2] ++ y) = e (x ++ [inr (k1 * k2)] ++ y)
t: forall (x y : Words) (z : G),
e (x ++ [inl (f z)] ++ y) = e (x ++ [inr (g z)] ++ y)
oh: forall x y : Words, e (x ++ [inl 1] ++ y) = e (x ++ y)
ok: forall x y : Words, e (x ++ [inr 1] ++ y) = e (x ++ y)
forall (x y : Words) (h1 h2 : H),
DPath (fun _ : amal_type => P) (amal_mu_H x y h1 h2)
  (e (x ++ [inl h1, inl h2] ++ y)) (e (x ++ [inl (h1 * h2)] ++ y))
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: Type
IsHSet0: IsHSet P
e: Words -> P
eh: forall (x y : Words) (h1 h2 : H),
e (x ++ [inl h1, inl h2] ++ y) = e (x ++ [inl (h1 * h2)] ++ y)
ek: forall (x y : Words) (k1 k2 : K),
e (x ++ [inr k1, inr k2] ++ y) = e (x ++ [inr (k1 * k2)] ++ y)
t: forall (x y : Words) (z : G),
e (x ++ [inl (f z)] ++ y) = e (x ++ [inr (g z)] ++ y)
oh: forall x y : Words, e (x ++ [inl 1] ++ y) = e (x ++ y)
ok: forall x y : Words, e (x ++ [inr 1] ++ y) = e (x ++ y)
forall (x y : Words) (k1 k2 : K),
DPath (fun _ : amal_type => P) (amal_mu_K x y k1 k2)
  (e (x ++ [inr k1, inr k2] ++ y)) (e (x ++ [inr (k1 * k2)] ++ y))
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: Type
IsHSet0: IsHSet P
e: Words -> P
eh: forall (x y : Words) (h1 h2 : H),
e (x ++ [inl h1, inl h2] ++ y) = e (x ++ [inl (h1 * h2)] ++ y)
ek: forall (x y : Words) (k1 k2 : K),
e (x ++ [inr k1, inr k2] ++ y) = e (x ++ [inr (k1 * k2)] ++ y)
t: forall (x y : Words) (z : G),
e (x ++ [inl (f z)] ++ y) = e (x ++ [inr (g z)] ++ y)
oh: forall x y : Words, e (x ++ [inl 1] ++ y) = e (x ++ y)
ok: forall x y : Words, e (x ++ [inr 1] ++ y) = e (x ++ y)
forall (x y : Words) (z : G),
DPath (fun _ : amal_type => P) (amal_tau x y z) (e (x ++ [inl (f z)] ++ y))
  (e (x ++ [inr (g z)] ++ y))
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: Type
IsHSet0: IsHSet P
e: Words -> P
eh: forall (x y : Words) (h1 h2 : H),
e (x ++ [inl h1, inl h2] ++ y) = e (x ++ [inl (h1 * h2)] ++ y)
ek: forall (x y : Words) (k1 k2 : K),
e (x ++ [inr k1, inr k2] ++ y) = e (x ++ [inr (k1 * k2)] ++ y)
t: forall (x y : Words) (z : G),
e (x ++ [inl (f z)] ++ y) = e (x ++ [inr (g z)] ++ y)
oh: forall x y : Words, e (x ++ [inl 1] ++ y) = e (x ++ y)
ok: forall x y : Words, e (x ++ [inr 1] ++ y) = e (x ++ y)
forall x y : Words,
DPath (fun _ : amal_type => P) (amal_omega_H x y) 
  (e (x ++ [inl 1] ++ y)) (e (x ++ y))
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: Type
IsHSet0: IsHSet P
e: Words -> P
eh: forall (x y : Words) (h1 h2 : H),
e (x ++ [inl h1, inl h2] ++ y) = e (x ++ [inl (h1 * h2)] ++ y)
ek: forall (x y : Words) (k1 k2 : K),
e (x ++ [inr k1, inr k2] ++ y) = e (x ++ [inr (k1 * k2)] ++ y)
t: forall (x y : Words) (z : G),
e (x ++ [inl (f z)] ++ y) = e (x ++ [inr (g z)] ++ y)
oh: forall x y : Words, e (x ++ [inl 1] ++ y) = e (x ++ y)
ok: forall x y : Words, e (x ++ [inr 1] ++ y) = e (x ++ y)
forall x y : Words,
DPath (fun _ : amal_type => P) (amal_omega_K x y) 
  (e (x ++ [inr 1] ++ y)) (e (x ++ y))
    all: intros; apply dp_const.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: Type
IsHSet0: IsHSet P
e: Words -> P
eh: forall (x0 y0 : Words) (h0 h3 : H),
e (x0 ++ [inl h0, inl h3] ++ y0) = e (x0 ++ [inl (h0 * h3)] ++ y0)
ek: forall (x0 y0 : Words) (k1 k2 : K),
e (x0 ++ [inr k1, inr k2] ++ y0) = e (x0 ++ [inr (k1 * k2)] ++ y0)
t: forall (x0 y0 : Words) (z : G),
e (x0 ++ [inl (f z)] ++ y0) = e (x0 ++ [inr (g z)] ++ y0)
oh: forall x0 y0 : Words, e (x0 ++ [inl 1] ++ y0) = e (x0 ++ y0)
ok: forall x0 y0 : Words, e (x0 ++ [inr 1] ++ y0) = e (x0 ++ y0)
x, y: Words
h1, h2: H
e (x ++ [inl h1, inl h2] ++ y) = e (x ++ [inl (h1 * h2)] ++ y)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: Type
IsHSet0: IsHSet P
e: Words -> P
eh: forall (x0 y0 : Words) (h1 h2 : H),
e (x0 ++ [inl h1, inl h2] ++ y0) = e (x0 ++ [inl (h1 * h2)] ++ y0)
ek: forall (x0 y0 : Words) (k0 k3 : K),
e (x0 ++ [inr k0, inr k3] ++ y0) = e (x0 ++ [inr (k0 * k3)] ++ y0)
t: forall (x0 y0 : Words) (z : G),
e (x0 ++ [inl (f z)] ++ y0) = e (x0 ++ [inr (g z)] ++ y0)
oh: forall x0 y0 : Words, e (x0 ++ [inl 1] ++ y0) = e (x0 ++ y0)
ok: forall x0 y0 : Words, e (x0 ++ [inr 1] ++ y0) = e (x0 ++ y0)
x, y: Words
k1, k2: K
e (x ++ [inr k1, inr k2] ++ y) = e (x ++ [inr (k1 * k2)] ++ y)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: Type
IsHSet0: IsHSet P
e: Words -> P
eh: forall (x0 y0 : Words) (h1 h2 : H),
e (x0 ++ [inl h1, inl h2] ++ y0) = e (x0 ++ [inl (h1 * h2)] ++ y0)
ek: forall (x0 y0 : Words) (k1 k2 : K),
e (x0 ++ [inr k1, inr k2] ++ y0) = e (x0 ++ [inr (k1 * k2)] ++ y0)
t: forall (x0 y0 : Words) (z0 : G),
e (x0 ++ [inl (f z0)] ++ y0) = e (x0 ++ [inr (g z0)] ++ y0)
oh: forall x0 y0 : Words, e (x0 ++ [inl 1] ++ y0) = e (x0 ++ y0)
ok: forall x0 y0 : Words, e (x0 ++ [inr 1] ++ y0) = e (x0 ++ y0)
x, y: Words
z: G
e (x ++ [inl (f z)] ++ y) = e (x ++ [inr (g z)] ++ y)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: Type
IsHSet0: IsHSet P
e: Words -> P
eh: forall (x0 y0 : Words) (h1 h2 : H),
e (x0 ++ [inl h1, inl h2] ++ y0) = e (x0 ++ [inl (h1 * h2)] ++ y0)
ek: forall (x0 y0 : Words) (k1 k2 : K),
e (x0 ++ [inr k1, inr k2] ++ y0) = e (x0 ++ [inr (k1 * k2)] ++ y0)
t: forall (x0 y0 : Words) (z : G),
e (x0 ++ [inl (f z)] ++ y0) = e (x0 ++ [inr (g z)] ++ y0)
oh: forall x0 y0 : Words, e (x0 ++ [inl 1] ++ y0) = e (x0 ++ y0)
ok: forall x0 y0 : Words, e (x0 ++ [inr 1] ++ y0) = e (x0 ++ y0)
x, y: Words
e (x ++ [inl 1] ++ y) = e (x ++ y)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: Type
IsHSet0: IsHSet P
e: Words -> P
eh: forall (x0 y0 : Words) (h1 h2 : H),
e (x0 ++ [inl h1, inl h2] ++ y0) = e (x0 ++ [inl (h1 * h2)] ++ y0)
ek: forall (x0 y0 : Words) (k1 k2 : K),
e (x0 ++ [inr k1, inr k2] ++ y0) = e (x0 ++ [inr (k1 * k2)] ++ y0)
t: forall (x0 y0 : Words) (z : G),
e (x0 ++ [inl (f z)] ++ y0) = e (x0 ++ [inr (g z)] ++ y0)
oh: forall x0 y0 : Words, e (x0 ++ [inl 1] ++ y0) = e (x0 ++ y0)
ok: forall x0 y0 : Words, e (x0 ++ [inr 1] ++ y0) = e (x0 ++ y0)
x, y: Words
e (x ++ [inr 1] ++ y) = e (x ++ y)
    1: apply eh.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: Type
IsHSet0: IsHSet P
e: Words -> P
eh: forall (x0 y0 : Words) (h1 h2 : H),
e (x0 ++ [inl h1, inl h2] ++ y0) = e (x0 ++ [inl (h1 * h2)] ++ y0)
ek: forall (x0 y0 : Words) (k0 k3 : K),
e (x0 ++ [inr k0, inr k3] ++ y0) = e (x0 ++ [inr (k0 * k3)] ++ y0)
t: forall (x0 y0 : Words) (z : G),
e (x0 ++ [inl (f z)] ++ y0) = e (x0 ++ [inr (g z)] ++ y0)
oh: forall x0 y0 : Words, e (x0 ++ [inl 1] ++ y0) = e (x0 ++ y0)
ok: forall x0 y0 : Words, e (x0 ++ [inr 1] ++ y0) = e (x0 ++ y0)
x, y: Words
k1, k2: K
e (x ++ [inr k1, inr k2] ++ y) = e (x ++ [inr (k1 * k2)] ++ y)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: Type
IsHSet0: IsHSet P
e: Words -> P
eh: forall (x0 y0 : Words) (h1 h2 : H),
e (x0 ++ [inl h1, inl h2] ++ y0) = e (x0 ++ [inl (h1 * h2)] ++ y0)
ek: forall (x0 y0 : Words) (k1 k2 : K),
e (x0 ++ [inr k1, inr k2] ++ y0) = e (x0 ++ [inr (k1 * k2)] ++ y0)
t: forall (x0 y0 : Words) (z0 : G),
e (x0 ++ [inl (f z0)] ++ y0) = e (x0 ++ [inr (g z0)] ++ y0)
oh: forall x0 y0 : Words, e (x0 ++ [inl 1] ++ y0) = e (x0 ++ y0)
ok: forall x0 y0 : Words, e (x0 ++ [inr 1] ++ y0) = e (x0 ++ y0)
x, y: Words
z: G
e (x ++ [inl (f z)] ++ y) = e (x ++ [inr (g z)] ++ y)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: Type
IsHSet0: IsHSet P
e: Words -> P
eh: forall (x0 y0 : Words) (h1 h2 : H),
e (x0 ++ [inl h1, inl h2] ++ y0) = e (x0 ++ [inl (h1 * h2)] ++ y0)
ek: forall (x0 y0 : Words) (k1 k2 : K),
e (x0 ++ [inr k1, inr k2] ++ y0) = e (x0 ++ [inr (k1 * k2)] ++ y0)
t: forall (x0 y0 : Words) (z : G),
e (x0 ++ [inl (f z)] ++ y0) = e (x0 ++ [inr (g z)] ++ y0)
oh: forall x0 y0 : Words, e (x0 ++ [inl 1] ++ y0) = e (x0 ++ y0)
ok: forall x0 y0 : Words, e (x0 ++ [inr 1] ++ y0) = e (x0 ++ y0)
x, y: Words
e (x ++ [inl 1] ++ y) = e (x ++ y)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: Type
IsHSet0: IsHSet P
e: Words -> P
eh: forall (x0 y0 : Words) (h1 h2 : H),
e (x0 ++ [inl h1, inl h2] ++ y0) = e (x0 ++ [inl (h1 * h2)] ++ y0)
ek: forall (x0 y0 : Words) (k1 k2 : K),
e (x0 ++ [inr k1, inr k2] ++ y0) = e (x0 ++ [inr (k1 * k2)] ++ y0)
t: forall (x0 y0 : Words) (z : G),
e (x0 ++ [inl (f z)] ++ y0) = e (x0 ++ [inr (g z)] ++ y0)
oh: forall x0 y0 : Words, e (x0 ++ [inl 1] ++ y0) = e (x0 ++ y0)
ok: forall x0 y0 : Words, e (x0 ++ [inr 1] ++ y0) = e (x0 ++ y0)
x, y: Words
e (x ++ [inr 1] ++ y) = e (x ++ y)
    1: apply ek.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: Type
IsHSet0: IsHSet P
e: Words -> P
eh: forall (x0 y0 : Words) (h1 h2 : H),
e (x0 ++ [inl h1, inl h2] ++ y0) = e (x0 ++ [inl (h1 * h2)] ++ y0)
ek: forall (x0 y0 : Words) (k1 k2 : K),
e (x0 ++ [inr k1, inr k2] ++ y0) = e (x0 ++ [inr (k1 * k2)] ++ y0)
t: forall (x0 y0 : Words) (z0 : G),
e (x0 ++ [inl (f z0)] ++ y0) = e (x0 ++ [inr (g z0)] ++ y0)
oh: forall x0 y0 : Words, e (x0 ++ [inl 1] ++ y0) = e (x0 ++ y0)
ok: forall x0 y0 : Words, e (x0 ++ [inr 1] ++ y0) = e (x0 ++ y0)
x, y: Words
z: G
e (x ++ [inl (f z)] ++ y) = e (x ++ [inr (g z)] ++ y)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: Type
IsHSet0: IsHSet P
e: Words -> P
eh: forall (x0 y0 : Words) (h1 h2 : H),
e (x0 ++ [inl h1, inl h2] ++ y0) = e (x0 ++ [inl (h1 * h2)] ++ y0)
ek: forall (x0 y0 : Words) (k1 k2 : K),
e (x0 ++ [inr k1, inr k2] ++ y0) = e (x0 ++ [inr (k1 * k2)] ++ y0)
t: forall (x0 y0 : Words) (z : G),
e (x0 ++ [inl (f z)] ++ y0) = e (x0 ++ [inr (g z)] ++ y0)
oh: forall x0 y0 : Words, e (x0 ++ [inl 1] ++ y0) = e (x0 ++ y0)
ok: forall x0 y0 : Words, e (x0 ++ [inr 1] ++ y0) = e (x0 ++ y0)
x, y: Words
e (x ++ [inl 1] ++ y) = e (x ++ y)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: Type
IsHSet0: IsHSet P
e: Words -> P
eh: forall (x0 y0 : Words) (h1 h2 : H),
e (x0 ++ [inl h1, inl h2] ++ y0) = e (x0 ++ [inl (h1 * h2)] ++ y0)
ek: forall (x0 y0 : Words) (k1 k2 : K),
e (x0 ++ [inr k1, inr k2] ++ y0) = e (x0 ++ [inr (k1 * k2)] ++ y0)
t: forall (x0 y0 : Words) (z : G),
e (x0 ++ [inl (f z)] ++ y0) = e (x0 ++ [inr (g z)] ++ y0)
oh: forall x0 y0 : Words, e (x0 ++ [inl 1] ++ y0) = e (x0 ++ y0)
ok: forall x0 y0 : Words, e (x0 ++ [inr 1] ++ y0) = e (x0 ++ y0)
x, y: Words
e (x ++ [inr 1] ++ y) = e (x ++ y)
    1: apply t.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: Type
IsHSet0: IsHSet P
e: Words -> P
eh: forall (x0 y0 : Words) (h1 h2 : H),
e (x0 ++ [inl h1, inl h2] ++ y0) = e (x0 ++ [inl (h1 * h2)] ++ y0)
ek: forall (x0 y0 : Words) (k1 k2 : K),
e (x0 ++ [inr k1, inr k2] ++ y0) = e (x0 ++ [inr (k1 * k2)] ++ y0)
t: forall (x0 y0 : Words) (z : G),
e (x0 ++ [inl (f z)] ++ y0) = e (x0 ++ [inr (g z)] ++ y0)
oh: forall x0 y0 : Words, e (x0 ++ [inl 1] ++ y0) = e (x0 ++ y0)
ok: forall x0 y0 : Words, e (x0 ++ [inr 1] ++ y0) = e (x0 ++ y0)
x, y: Words
e (x ++ [inl 1] ++ y) = e (x ++ y)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: Type
IsHSet0: IsHSet P
e: Words -> P
eh: forall (x0 y0 : Words) (h1 h2 : H),
e (x0 ++ [inl h1, inl h2] ++ y0) = e (x0 ++ [inl (h1 * h2)] ++ y0)
ek: forall (x0 y0 : Words) (k1 k2 : K),
e (x0 ++ [inr k1, inr k2] ++ y0) = e (x0 ++ [inr (k1 * k2)] ++ y0)
t: forall (x0 y0 : Words) (z : G),
e (x0 ++ [inl (f z)] ++ y0) = e (x0 ++ [inr (g z)] ++ y0)
oh: forall x0 y0 : Words, e (x0 ++ [inl 1] ++ y0) = e (x0 ++ y0)
ok: forall x0 y0 : Words, e (x0 ++ [inr 1] ++ y0) = e (x0 ++ y0)
x, y: Words
e (x ++ [inr 1] ++ y) = e (x ++ y)
    1: apply oh.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: Type
IsHSet0: IsHSet P
e: Words -> P
eh: forall (x0 y0 : Words) (h1 h2 : H),
e (x0 ++ [inl h1, inl h2] ++ y0) = e (x0 ++ [inl (h1 * h2)] ++ y0)
ek: forall (x0 y0 : Words) (k1 k2 : K),
e (x0 ++ [inr k1, inr k2] ++ y0) = e (x0 ++ [inr (k1 * k2)] ++ y0)
t: forall (x0 y0 : Words) (z : G),
e (x0 ++ [inl (f z)] ++ y0) = e (x0 ++ [inr (g z)] ++ y0)
oh: forall x0 y0 : Words, e (x0 ++ [inl 1] ++ y0) = e (x0 ++ y0)
ok: forall x0 y0 : Words, e (x0 ++ [inr 1] ++ y0) = e (x0 ++ y0)
x, y: Words
e (x ++ [inr 1] ++ y) = e (x ++ y)
    apply ok.
  Defined.

  (** Now for the group structure *)

  (** We will frequently need to use that path types in [amal_type] are hprops, and so it speeds things up to create this instance.  It is fast to use [_] here, but when the terms are large below, it becomes slower. *)
  Local Instance ishprop_paths_amal_type (x y : amal_type) : IsHProp (x = y) := _.

  (** The group operation is concatenation of the underlying list. Most of the work is spent showing that it respects the path constructors. *)
  Local Instance sgop_amal_type : SgOp amal_type.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
SgOp amal_type
  Proof.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
SgOp amal_type
    intros x y; revert x.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
y: amal_type
amal_type -> amal_type
    snapply amal_type_rec; only 1: exact _; intros x; revert y.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: Words
amal_type -> amal_type
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: Words
forall (y : amal_type) (y0 : Words) (h1 h2 : H),
(fun x0 : Words => ?Goal@{x:=x0} y) (x ++ [inl h1, inl h2] ++ y0) =
(fun x0 : Words => ?Goal@{x:=x0} y) (x ++ [inl (h1 * h2)] ++ y0)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: Words
forall (y : amal_type) (y0 : Words) (k1 k2 : K),
(fun x0 : Words => ?Goal@{x:=x0} y) (x ++ [inr k1, inr k2] ++ y0) =
(fun x0 : Words => ?Goal@{x:=x0} y) (x ++ [inr (k1 * k2)] ++ y0)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: Words
forall (y : amal_type) (y0 : Words) (z : G),
(fun x0 : Words => ?Goal@{x:=x0} y) (x ++ [inl (f z)] ++ y0) =
(fun x0 : Words => ?Goal@{x:=x0} y) (x ++ [inr (g z)] ++ y0)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: Words
forall (y : amal_type) (y0 : Words),
(fun x0 : Words => ?Goal@{x:=x0} y) (x ++ [inl 1] ++ y0) =
(fun x0 : Words => ?Goal@{x:=x0} y) (x ++ y0)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: Words
forall (y : amal_type) (y0 : Words),
(fun x0 : Words => ?Goal@{x:=x0} y) (x ++ [inr 1] ++ y0) =
(fun x0 : Words => ?Goal@{x:=x0} y) (x ++ y0)
    {
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: Words
amal_type -> amal_type snapply amal_type_rec; only 1: exact _; intros y.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
amal_type
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
forall (y0 : Words) (h1 h2 : H),
(fun y1 : Words => ?Goal4@{y:=y1}) (y ++ [inl h1, inl h2] ++ y0) =
(fun y1 : Words => ?Goal4@{y:=y1}) (y ++ [inl (h1 * h2)] ++ y0)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
forall (y0 : Words) (k1 k2 : K),
(fun y1 : Words => ?Goal4@{y:=y1}) (y ++ [inr k1, inr k2] ++ y0) =
(fun y1 : Words => ?Goal4@{y:=y1}) (y ++ [inr (k1 * k2)] ++ y0)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
forall (y0 : Words) (z : G),
(fun y1 : Words => ?Goal4@{y:=y1}) (y ++ [inl (f z)] ++ y0) =
(fun y1 : Words => ?Goal4@{y:=y1}) (y ++ [inr (g z)] ++ y0)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
forall y0 : Words,
(fun y1 : Words => ?Goal4@{y:=y1}) (y ++ [inl 1] ++ y0) =
(fun y1 : Words => ?Goal4@{y:=y1}) (y ++ y0)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
forall y0 : Words,
(fun y1 : Words => ?Goal4@{y:=y1}) (y ++ [inr 1] ++ y0) =
(fun y1 : Words => ?Goal4@{y:=y1}) (y ++ y0)
      1: exact (amal_eta (x ++ y)).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
forall (y0 : Words) (h1 h2 : H),
(fun y1 : Words => amal_eta (x ++ y1)) (y ++ [inl h1, inl h2] ++ y0) =
(fun y1 : Words => amal_eta (x ++ y1)) (y ++ [inl (h1 * h2)] ++ y0)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
forall (y0 : Words) (k1 k2 : K),
(fun y1 : Words => amal_eta (x ++ y1)) (y ++ [inr k1, inr k2] ++ y0) =
(fun y1 : Words => amal_eta (x ++ y1)) (y ++ [inr (k1 * k2)] ++ y0)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
forall (y0 : Words) (z : G),
(fun y1 : Words => amal_eta (x ++ y1)) (y ++ [inl (f z)] ++ y0) =
(fun y1 : Words => amal_eta (x ++ y1)) (y ++ [inr (g z)] ++ y0)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
forall y0 : Words,
(fun y1 : Words => amal_eta (x ++ y1)) (y ++ [inl 1] ++ y0) =
(fun y1 : Words => amal_eta (x ++ y1)) (y ++ y0)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
forall y0 : Words,
(fun y1 : Words => amal_eta (x ++ y1)) (y ++ [inr 1] ++ y0) =
(fun y1 : Words => amal_eta (x ++ y1)) (y ++ y0)
      {
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
forall (y0 : Words) (h1 h2 : H),
(fun y1 : Words => amal_eta (x ++ y1)) (y ++ [inl h1, inl h2] ++ y0) =
(fun y1 : Words => amal_eta (x ++ y1)) (y ++ [inl (h1 * h2)] ++ y0) intros z h1 h2.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y, z: Words
h1, h2: H
(fun y0 : Words => amal_eta (x ++ y0)) (y ++ [inl h1, inl h2] ++ z) =
(fun y0 : Words => amal_eta (x ++ y0)) (y ++ [inl (h1 * h2)] ++ z)
        refine (ap amal_eta _ @ _ @ ap amal_eta _^).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y, z: Words
h1, h2: H
x ++ y ++ [inl h1, inl h2] ++ z = ?Goal8
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y, z: Words
h1, h2: H
amal_eta ?Goal8 = amal_eta ?Goal11
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y, z: Words
h1, h2: H
x ++ y ++ [inl (h1 * h2)] ++ z = ?Goal11
        1,3: apply app_assoc.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y, z: Words
h1, h2: H
amal_eta ((x ++ y) ++ [inl h1, inl h2] ++ z) =
amal_eta ((x ++ y) ++ [inl (h1 * h2)] ++ z)
        rapply amal_mu_H. }
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
forall (y0 : Words) (k1 k2 : K),
(fun y1 : Words => amal_eta (x ++ y1)) (y ++ [inr k1, inr k2] ++ y0) =
(fun y1 : Words => amal_eta (x ++ y1)) (y ++ [inr (k1 * k2)] ++ y0)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
forall (y0 : Words) (z : G),
(fun y1 : Words => amal_eta (x ++ y1)) (y ++ [inl (f z)] ++ y0) =
(fun y1 : Words => amal_eta (x ++ y1)) (y ++ [inr (g z)] ++ y0)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
forall y0 : Words,
(fun y1 : Words => amal_eta (x ++ y1)) (y ++ [inl 1] ++ y0) =
(fun y1 : Words => amal_eta (x ++ y1)) (y ++ y0)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
forall y0 : Words,
(fun y1 : Words => amal_eta (x ++ y1)) (y ++ [inr 1] ++ y0) =
(fun y1 : Words => amal_eta (x ++ y1)) (y ++ y0)
      {
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
forall (y0 : Words) (k1 k2 : K),
(fun y1 : Words => amal_eta (x ++ y1)) (y ++ [inr k1, inr k2] ++ y0) =
(fun y1 : Words => amal_eta (x ++ y1)) (y ++ [inr (k1 * k2)] ++ y0) intros z k1 k2.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y, z: Words
k1, k2: K
(fun y0 : Words => amal_eta (x ++ y0)) (y ++ [inr k1, inr k2] ++ z) =
(fun y0 : Words => amal_eta (x ++ y0)) (y ++ [inr (k1 * k2)] ++ z)
        refine (ap amal_eta _ @ _ @ ap amal_eta _^).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y, z: Words
k1, k2: K
x ++ y ++ [inr k1, inr k2] ++ z = ?Goal7
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y, z: Words
k1, k2: K
amal_eta ?Goal7 = amal_eta ?Goal10
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y, z: Words
k1, k2: K
x ++ y ++ [inr (k1 * k2)] ++ z = ?Goal10
        1,3: apply app_assoc.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y, z: Words
k1, k2: K
amal_eta ((x ++ y) ++ [inr k1, inr k2] ++ z) =
amal_eta ((x ++ y) ++ [inr (k1 * k2)] ++ z)
        rapply amal_mu_K. }
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
forall (y0 : Words) (z : G),
(fun y1 : Words => amal_eta (x ++ y1)) (y ++ [inl (f z)] ++ y0) =
(fun y1 : Words => amal_eta (x ++ y1)) (y ++ [inr (g z)] ++ y0)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
forall y0 : Words,
(fun y1 : Words => amal_eta (x ++ y1)) (y ++ [inl 1] ++ y0) =
(fun y1 : Words => amal_eta (x ++ y1)) (y ++ y0)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
forall y0 : Words,
(fun y1 : Words => amal_eta (x ++ y1)) (y ++ [inr 1] ++ y0) =
(fun y1 : Words => amal_eta (x ++ y1)) (y ++ y0)
      {
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
forall (y0 : Words) (z : G),
(fun y1 : Words => amal_eta (x ++ y1)) (y ++ [inl (f z)] ++ y0) =
(fun y1 : Words => amal_eta (x ++ y1)) (y ++ [inr (g z)] ++ y0) intros w z.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y, w: Words
z: G
(fun y0 : Words => amal_eta (x ++ y0)) (y ++ [inl (f z)] ++ w) =
(fun y0 : Words => amal_eta (x ++ y0)) (y ++ [inr (g z)] ++ w)
        refine (ap amal_eta _ @ _ @ ap amal_eta _^).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y, w: Words
z: G
x ++ y ++ [inl (f z)] ++ w = ?Goal6
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y, w: Words
z: G
amal_eta ?Goal6 = amal_eta ?Goal9
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y, w: Words
z: G
x ++ y ++ [inr (g z)] ++ w = ?Goal9
        1,3: apply app_assoc.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y, w: Words
z: G
amal_eta ((x ++ y) ++ [inl (f z)] ++ w) =
amal_eta ((x ++ y) ++ [inr (g z)] ++ w)
        apply amal_tau. }
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
forall y0 : Words,
(fun y1 : Words => amal_eta (x ++ y1)) (y ++ [inl 1] ++ y0) =
(fun y1 : Words => amal_eta (x ++ y1)) (y ++ y0)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
forall y0 : Words,
(fun y1 : Words => amal_eta (x ++ y1)) (y ++ [inr 1] ++ y0) =
(fun y1 : Words => amal_eta (x ++ y1)) (y ++ y0)
      {
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
forall y0 : Words,
(fun y1 : Words => amal_eta (x ++ y1)) (y ++ [inl 1] ++ y0) =
(fun y1 : Words => amal_eta (x ++ y1)) (y ++ y0) intros z.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y, z: Words
(fun y0 : Words => amal_eta (x ++ y0)) (y ++ [inl 1] ++ z) =
(fun y0 : Words => amal_eta (x ++ y0)) (y ++ z)
        refine (ap amal_eta _ @ _ @ ap amal_eta _^).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y, z: Words
x ++ y ++ [inl 1] ++ z = ?Goal5
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y, z: Words
amal_eta ?Goal5 = amal_eta ?Goal8
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y, z: Words
x ++ y ++ z = ?Goal8
        1,3: apply app_assoc.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y, z: Words
amal_eta ((x ++ y) ++ [inl 1] ++ z) = amal_eta ((x ++ y) ++ z)
        apply amal_omega_H. }
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
forall y0 : Words,
(fun y1 : Words => amal_eta (x ++ y1)) (y ++ [inr 1] ++ y0) =
(fun y1 : Words => amal_eta (x ++ y1)) (y ++ y0)
      {
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
forall y0 : Words,
(fun y1 : Words => amal_eta (x ++ y1)) (y ++ [inr 1] ++ y0) =
(fun y1 : Words => amal_eta (x ++ y1)) (y ++ y0) intros z.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y, z: Words
(fun y0 : Words => amal_eta (x ++ y0)) (y ++ [inr 1] ++ z) =
(fun y0 : Words => amal_eta (x ++ y0)) (y ++ z)
        refine (ap amal_eta _ @ _ @ ap amal_eta _^).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y, z: Words
x ++ y ++ [inr 1] ++ z = ?Goal4
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y, z: Words
amal_eta ?Goal4 = amal_eta ?Goal7
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y, z: Words
x ++ y ++ z = ?Goal7
        1,3: apply app_assoc.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y, z: Words
amal_eta ((x ++ y) ++ [inr 1] ++ z) = amal_eta ((x ++ y) ++ z)
        apply amal_omega_K. } }
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: Words
forall (y : amal_type) (y0 : Words) (h1 h2 : H),
(fun x0 : Words =>
 amal_type_rec amal_type (fun y1 : Words => amal_eta (x0 ++ y1))
   (fun (y1 z : Words) (h0 h3 : H) =>
    (ap amal_eta (app_assoc x0 y1 ([inl h0, inl h3] ++ z)) @
     amal_mu_H (x0 ++ y1) z h0 h3) @
    ap amal_eta (app_assoc x0 y1 ([inl (h0 * h3)] ++ z))^)
   (fun (y1 z : Words) (k1 k2 : K) =>
    (ap amal_eta (app_assoc x0 y1 ([inr k1, inr k2] ++ z)) @
     amal_mu_K (x0 ++ y1) z k1 k2) @
    ap amal_eta (app_assoc x0 y1 ([inr (k1 * k2)] ++ z))^)
   (fun (y1 w : Words) (z : G) =>
    (ap amal_eta (app_assoc x0 y1 ([inl (f z)] ++ w)) @
     amal_tau (x0 ++ y1) w z) @
    ap amal_eta (app_assoc x0 y1 ([inr (g z)] ++ w))^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inl mon_unit] ++ z)) @
     amal_omega_H (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inr mon_unit] ++ z)) @
     amal_omega_K (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   y)
  (x ++ [inl h1, inl h2] ++ y0) =
(fun x0 : Words =>
 amal_type_rec amal_type (fun y1 : Words => amal_eta (x0 ++ y1))
   (fun (y1 z : Words) (h0 h3 : H) =>
    (ap amal_eta (app_assoc x0 y1 ([inl h0, inl h3] ++ z)) @
     amal_mu_H (x0 ++ y1) z h0 h3) @
    ap amal_eta (app_assoc x0 y1 ([inl (h0 * h3)] ++ z))^)
   (fun (y1 z : Words) (k1 k2 : K) =>
    (ap amal_eta (app_assoc x0 y1 ([inr k1, inr k2] ++ z)) @
     amal_mu_K (x0 ++ y1) z k1 k2) @
    ap amal_eta (app_assoc x0 y1 ([inr (k1 * k2)] ++ z))^)
   (fun (y1 w : Words) (z : G) =>
    (ap amal_eta (app_assoc x0 y1 ([inl (f z)] ++ w)) @
     amal_tau (x0 ++ y1) w z) @
    ap amal_eta (app_assoc x0 y1 ([inr (g z)] ++ w))^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inl mon_unit] ++ z)) @
     amal_omega_H (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inr mon_unit] ++ z)) @
     amal_omega_K (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   y)
  (x ++ [inl (h1 * h2)] ++ y0)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: Words
forall (y : amal_type) (y0 : Words) (k1 k2 : K),
(fun x0 : Words =>
 amal_type_rec amal_type (fun y1 : Words => amal_eta (x0 ++ y1))
   (fun (y1 z : Words) (h1 h2 : H) =>
    (ap amal_eta (app_assoc x0 y1 ([inl h1, inl h2] ++ z)) @
     amal_mu_H (x0 ++ y1) z h1 h2) @
    ap amal_eta (app_assoc x0 y1 ([inl (h1 * h2)] ++ z))^)
   (fun (y1 z : Words) (k0 k3 : K) =>
    (ap amal_eta (app_assoc x0 y1 ([inr k0, inr k3] ++ z)) @
     amal_mu_K (x0 ++ y1) z k0 k3) @
    ap amal_eta (app_assoc x0 y1 ([inr (k0 * k3)] ++ z))^)
   (fun (y1 w : Words) (z : G) =>
    (ap amal_eta (app_assoc x0 y1 ([inl (f z)] ++ w)) @
     amal_tau (x0 ++ y1) w z) @
    ap amal_eta (app_assoc x0 y1 ([inr (g z)] ++ w))^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inl mon_unit] ++ z)) @
     amal_omega_H (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inr mon_unit] ++ z)) @
     amal_omega_K (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   y)
  (x ++ [inr k1, inr k2] ++ y0) =
(fun x0 : Words =>
 amal_type_rec amal_type (fun y1 : Words => amal_eta (x0 ++ y1))
   (fun (y1 z : Words) (h1 h2 : H) =>
    (ap amal_eta (app_assoc x0 y1 ([inl h1, inl h2] ++ z)) @
     amal_mu_H (x0 ++ y1) z h1 h2) @
    ap amal_eta (app_assoc x0 y1 ([inl (h1 * h2)] ++ z))^)
   (fun (y1 z : Words) (k0 k3 : K) =>
    (ap amal_eta (app_assoc x0 y1 ([inr k0, inr k3] ++ z)) @
     amal_mu_K (x0 ++ y1) z k0 k3) @
    ap amal_eta (app_assoc x0 y1 ([inr (k0 * k3)] ++ z))^)
   (fun (y1 w : Words) (z : G) =>
    (ap amal_eta (app_assoc x0 y1 ([inl (f z)] ++ w)) @
     amal_tau (x0 ++ y1) w z) @
    ap amal_eta (app_assoc x0 y1 ([inr (g z)] ++ w))^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inl mon_unit] ++ z)) @
     amal_omega_H (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inr mon_unit] ++ z)) @
     amal_omega_K (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   y)
  (x ++ [inr (k1 * k2)] ++ y0)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: Words
forall (y : amal_type) (y0 : Words) (z : G),
(fun x0 : Words =>
 amal_type_rec amal_type (fun y1 : Words => amal_eta (x0 ++ y1))
   (fun (y1 z0 : Words) (h1 h2 : H) =>
    (ap amal_eta (app_assoc x0 y1 ([inl h1, inl h2] ++ z0)) @
     amal_mu_H (x0 ++ y1) z0 h1 h2) @
    ap amal_eta (app_assoc x0 y1 ([inl (h1 * h2)] ++ z0))^)
   (fun (y1 z0 : Words) (k1 k2 : K) =>
    (ap amal_eta (app_assoc x0 y1 ([inr k1, inr k2] ++ z0)) @
     amal_mu_K (x0 ++ y1) z0 k1 k2) @
    ap amal_eta (app_assoc x0 y1 ([inr (k1 * k2)] ++ z0))^)
   (fun (y1 w : Words) (z0 : G) =>
    (ap amal_eta (app_assoc x0 y1 ([inl (f z0)] ++ w)) @
     amal_tau (x0 ++ y1) w z0) @
    ap amal_eta (app_assoc x0 y1 ([inr (g z0)] ++ w))^)
   (fun y1 z0 : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inl mon_unit] ++ z0)) @
     amal_omega_H (x0 ++ y1) z0) @
    ap amal_eta (app_assoc x0 y1 z0)^)
   (fun y1 z0 : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inr mon_unit] ++ z0)) @
     amal_omega_K (x0 ++ y1) z0) @
    ap amal_eta (app_assoc x0 y1 z0)^)
   y)
  (x ++ [inl (f z)] ++ y0) =
(fun x0 : Words =>
 amal_type_rec amal_type (fun y1 : Words => amal_eta (x0 ++ y1))
   (fun (y1 z0 : Words) (h1 h2 : H) =>
    (ap amal_eta (app_assoc x0 y1 ([inl h1, inl h2] ++ z0)) @
     amal_mu_H (x0 ++ y1) z0 h1 h2) @
    ap amal_eta (app_assoc x0 y1 ([inl (h1 * h2)] ++ z0))^)
   (fun (y1 z0 : Words) (k1 k2 : K) =>
    (ap amal_eta (app_assoc x0 y1 ([inr k1, inr k2] ++ z0)) @
     amal_mu_K (x0 ++ y1) z0 k1 k2) @
    ap amal_eta (app_assoc x0 y1 ([inr (k1 * k2)] ++ z0))^)
   (fun (y1 w : Words) (z0 : G) =>
    (ap amal_eta (app_assoc x0 y1 ([inl (f z0)] ++ w)) @
     amal_tau (x0 ++ y1) w z0) @
    ap amal_eta (app_assoc x0 y1 ([inr (g z0)] ++ w))^)
   (fun y1 z0 : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inl mon_unit] ++ z0)) @
     amal_omega_H (x0 ++ y1) z0) @
    ap amal_eta (app_assoc x0 y1 z0)^)
   (fun y1 z0 : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inr mon_unit] ++ z0)) @
     amal_omega_K (x0 ++ y1) z0) @
    ap amal_eta (app_assoc x0 y1 z0)^)
   y)
  (x ++ [inr (g z)] ++ y0)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: Words
forall (y : amal_type) (y0 : Words),
(fun x0 : Words =>
 amal_type_rec amal_type (fun y1 : Words => amal_eta (x0 ++ y1))
   (fun (y1 z : Words) (h1 h2 : H) =>
    (ap amal_eta (app_assoc x0 y1 ([inl h1, inl h2] ++ z)) @
     amal_mu_H (x0 ++ y1) z h1 h2) @
    ap amal_eta (app_assoc x0 y1 ([inl (h1 * h2)] ++ z))^)
   (fun (y1 z : Words) (k1 k2 : K) =>
    (ap amal_eta (app_assoc x0 y1 ([inr k1, inr k2] ++ z)) @
     amal_mu_K (x0 ++ y1) z k1 k2) @
    ap amal_eta (app_assoc x0 y1 ([inr (k1 * k2)] ++ z))^)
   (fun (y1 w : Words) (z : G) =>
    (ap amal_eta (app_assoc x0 y1 ([inl (f z)] ++ w)) @
     amal_tau (x0 ++ y1) w z) @
    ap amal_eta (app_assoc x0 y1 ([inr (g z)] ++ w))^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inl mon_unit] ++ z)) @
     amal_omega_H (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inr mon_unit] ++ z)) @
     amal_omega_K (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   y)
  (x ++ [inl 1] ++ y0) =
(fun x0 : Words =>
 amal_type_rec amal_type (fun y1 : Words => amal_eta (x0 ++ y1))
   (fun (y1 z : Words) (h1 h2 : H) =>
    (ap amal_eta (app_assoc x0 y1 ([inl h1, inl h2] ++ z)) @
     amal_mu_H (x0 ++ y1) z h1 h2) @
    ap amal_eta (app_assoc x0 y1 ([inl (h1 * h2)] ++ z))^)
   (fun (y1 z : Words) (k1 k2 : K) =>
    (ap amal_eta (app_assoc x0 y1 ([inr k1, inr k2] ++ z)) @
     amal_mu_K (x0 ++ y1) z k1 k2) @
    ap amal_eta (app_assoc x0 y1 ([inr (k1 * k2)] ++ z))^)
   (fun (y1 w : Words) (z : G) =>
    (ap amal_eta (app_assoc x0 y1 ([inl (f z)] ++ w)) @
     amal_tau (x0 ++ y1) w z) @
    ap amal_eta (app_assoc x0 y1 ([inr (g z)] ++ w))^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inl mon_unit] ++ z)) @
     amal_omega_H (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inr mon_unit] ++ z)) @
     amal_omega_K (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   y)
  (x ++ y0)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: Words
forall (y : amal_type) (y0 : Words),
(fun x0 : Words =>
 amal_type_rec amal_type (fun y1 : Words => amal_eta (x0 ++ y1))
   (fun (y1 z : Words) (h1 h2 : H) =>
    (ap amal_eta (app_assoc x0 y1 ([inl h1, inl h2] ++ z)) @
     amal_mu_H (x0 ++ y1) z h1 h2) @
    ap amal_eta (app_assoc x0 y1 ([inl (h1 * h2)] ++ z))^)
   (fun (y1 z : Words) (k1 k2 : K) =>
    (ap amal_eta (app_assoc x0 y1 ([inr k1, inr k2] ++ z)) @
     amal_mu_K (x0 ++ y1) z k1 k2) @
    ap amal_eta (app_assoc x0 y1 ([inr (k1 * k2)] ++ z))^)
   (fun (y1 w : Words) (z : G) =>
    (ap amal_eta (app_assoc x0 y1 ([inl (f z)] ++ w)) @
     amal_tau (x0 ++ y1) w z) @
    ap amal_eta (app_assoc x0 y1 ([inr (g z)] ++ w))^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inl mon_unit] ++ z)) @
     amal_omega_H (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inr mon_unit] ++ z)) @
     amal_omega_K (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   y)
  (x ++ [inr 1] ++ y0) =
(fun x0 : Words =>
 amal_type_rec amal_type (fun y1 : Words => amal_eta (x0 ++ y1))
   (fun (y1 z : Words) (h1 h2 : H) =>
    (ap amal_eta (app_assoc x0 y1 ([inl h1, inl h2] ++ z)) @
     amal_mu_H (x0 ++ y1) z h1 h2) @
    ap amal_eta (app_assoc x0 y1 ([inl (h1 * h2)] ++ z))^)
   (fun (y1 z : Words) (k1 k2 : K) =>
    (ap amal_eta (app_assoc x0 y1 ([inr k1, inr k2] ++ z)) @
     amal_mu_K (x0 ++ y1) z k1 k2) @
    ap amal_eta (app_assoc x0 y1 ([inr (k1 * k2)] ++ z))^)
   (fun (y1 w : Words) (z : G) =>
    (ap amal_eta (app_assoc x0 y1 ([inl (f z)] ++ w)) @
     amal_tau (x0 ++ y1) w z) @
    ap amal_eta (app_assoc x0 y1 ([inr (g z)] ++ w))^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inl mon_unit] ++ z)) @
     amal_omega_H (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inr mon_unit] ++ z)) @
     amal_omega_K (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   y)
  (x ++ y0)
    {
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: Words
forall (y : amal_type) (y0 : Words) (h1 h2 : H),
(fun x0 : Words =>
 amal_type_rec amal_type (fun y1 : Words => amal_eta (x0 ++ y1))
   (fun (y1 z : Words) (h0 h3 : H) =>
    (ap amal_eta (app_assoc x0 y1 ([inl h0, inl h3] ++ z)) @
     amal_mu_H (x0 ++ y1) z h0 h3) @
    ap amal_eta (app_assoc x0 y1 ([inl (h0 * h3)] ++ z))^)
   (fun (y1 z : Words) (k1 k2 : K) =>
    (ap amal_eta (app_assoc x0 y1 ([inr k1, inr k2] ++ z)) @
     amal_mu_K (x0 ++ y1) z k1 k2) @
    ap amal_eta (app_assoc x0 y1 ([inr (k1 * k2)] ++ z))^)
   (fun (y1 w : Words) (z : G) =>
    (ap amal_eta (app_assoc x0 y1 ([inl (f z)] ++ w)) @
     amal_tau (x0 ++ y1) w z) @
    ap amal_eta (app_assoc x0 y1 ([inr (g z)] ++ w))^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inl mon_unit] ++ z)) @
     amal_omega_H (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inr mon_unit] ++ z)) @
     amal_omega_K (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   y)
  (x ++ [inl h1, inl h2] ++ y0) =
(fun x0 : Words =>
 amal_type_rec amal_type (fun y1 : Words => amal_eta (x0 ++ y1))
   (fun (y1 z : Words) (h0 h3 : H) =>
    (ap amal_eta (app_assoc x0 y1 ([inl h0, inl h3] ++ z)) @
     amal_mu_H (x0 ++ y1) z h0 h3) @
    ap amal_eta (app_assoc x0 y1 ([inl (h0 * h3)] ++ z))^)
   (fun (y1 z : Words) (k1 k2 : K) =>
    (ap amal_eta (app_assoc x0 y1 ([inr k1, inr k2] ++ z)) @
     amal_mu_K (x0 ++ y1) z k1 k2) @
    ap amal_eta (app_assoc x0 y1 ([inr (k1 * k2)] ++ z))^)
   (fun (y1 w : Words) (z : G) =>
    (ap amal_eta (app_assoc x0 y1 ([inl (f z)] ++ w)) @
     amal_tau (x0 ++ y1) w z) @
    ap amal_eta (app_assoc x0 y1 ([inr (g z)] ++ w))^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inl mon_unit] ++ z)) @
     amal_omega_H (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inr mon_unit] ++ z)) @
     amal_omega_K (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   y)
  (x ++ [inl (h1 * h2)] ++ y0) intros r y h1 h2; revert r.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
h1, h2: H
forall r : amal_type,
(fun x0 : Words =>
 amal_type_rec amal_type (fun y0 : Words => amal_eta (x0 ++ y0))
   (fun (y0 z : Words) (h0 h3 : H) =>
    (ap amal_eta (app_assoc x0 y0 ([inl h0, inl h3] ++ z)) @
     amal_mu_H (x0 ++ y0) z h0 h3) @
    ap amal_eta (app_assoc x0 y0 ([inl (h0 * h3)] ++ z))^)
   (fun (y0 z : Words) (k1 k2 : K) =>
    (ap amal_eta (app_assoc x0 y0 ([inr k1, inr k2] ++ z)) @
     amal_mu_K (x0 ++ y0) z k1 k2) @
    ap amal_eta (app_assoc x0 y0 ([inr (k1 * k2)] ++ z))^)
   (fun (y0 w : Words) (z : G) =>
    (ap amal_eta (app_assoc x0 y0 ([inl (f z)] ++ w)) @
     amal_tau (x0 ++ y0) w z) @
    ap amal_eta (app_assoc x0 y0 ([inr (g z)] ++ w))^)
   (fun y0 z : Words =>
    (ap amal_eta (app_assoc x0 y0 ([inl mon_unit] ++ z)) @
     amal_omega_H (x0 ++ y0) z) @
    ap amal_eta (app_assoc x0 y0 z)^)
   (fun y0 z : Words =>
    (ap amal_eta (app_assoc x0 y0 ([inr mon_unit] ++ z)) @
     amal_omega_K (x0 ++ y0) z) @
    ap amal_eta (app_assoc x0 y0 z)^)
   r)
  (x ++ [inl h1, inl h2] ++ y) =
(fun x0 : Words =>
 amal_type_rec amal_type (fun y0 : Words => amal_eta (x0 ++ y0))
   (fun (y0 z : Words) (h0 h3 : H) =>
    (ap amal_eta (app_assoc x0 y0 ([inl h0, inl h3] ++ z)) @
     amal_mu_H (x0 ++ y0) z h0 h3) @
    ap amal_eta (app_assoc x0 y0 ([inl (h0 * h3)] ++ z))^)
   (fun (y0 z : Words) (k1 k2 : K) =>
    (ap amal_eta (app_assoc x0 y0 ([inr k1, inr k2] ++ z)) @
     amal_mu_K (x0 ++ y0) z k1 k2) @
    ap amal_eta (app_assoc x0 y0 ([inr (k1 * k2)] ++ z))^)
   (fun (y0 w : Words) (z : G) =>
    (ap amal_eta (app_assoc x0 y0 ([inl (f z)] ++ w)) @
     amal_tau (x0 ++ y0) w z) @
    ap amal_eta (app_assoc x0 y0 ([inr (g z)] ++ w))^)
   (fun y0 z : Words =>
    (ap amal_eta (app_assoc x0 y0 ([inl mon_unit] ++ z)) @
     amal_omega_H (x0 ++ y0) z) @
    ap amal_eta (app_assoc x0 y0 z)^)
   (fun y0 z : Words =>
    (ap amal_eta (app_assoc x0 y0 ([inr mon_unit] ++ z)) @
     amal_omega_K (x0 ++ y0) z) @
    ap amal_eta (app_assoc x0 y0 z)^)
   r)
  (x ++ [inl (h1 * h2)] ++ y)
      rapply amal_type_ind_hprop.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
h1, h2: H
forall w : Words,
amal_type_rec amal_type
  (fun y0 : Words => amal_eta ((x ++ [inl h1, inl h2] ++ y) ++ y0))
  (fun (y0 z : Words) (h0 h3 : H) =>
   (ap amal_eta
      (app_assoc (x ++ [inl h1, inl h2] ++ y) y0 ([inl h0, inl h3] ++ z)) @
    amal_mu_H ((x ++ [inl h1, inl h2] ++ y) ++ y0) z h0 h3) @
   ap amal_eta
     (app_assoc (x ++ [inl h1, inl h2] ++ y) y0 ([inl (h0 * h3)] ++ z))^)
  (fun (y0 z : Words) (k1 k2 : K) =>
   (ap amal_eta
      (app_assoc (x ++ [inl h1, inl h2] ++ y) y0 ([inr k1, inr k2] ++ z)) @
    amal_mu_K ((x ++ [inl h1, inl h2] ++ y) ++ y0) z k1 k2) @
   ap amal_eta
     (app_assoc (x ++ [inl h1, inl h2] ++ y) y0 ([inr (k1 * k2)] ++ z))^)
  (fun (y0 w0 : Words) (z : G) =>
   (ap amal_eta
      (app_assoc (x ++ [inl h1, inl h2] ++ y) y0 ([inl (f z)] ++ w0)) @
    amal_tau ((x ++ [inl h1, inl h2] ++ y) ++ y0) w0 z) @
   ap amal_eta
     (app_assoc (x ++ [inl h1, inl h2] ++ y) y0 ([inr (g z)] ++ w0))^)
  (fun y0 z : Words =>
   (ap amal_eta
      (app_assoc (x ++ [inl h1, inl h2] ++ y) y0 ([inl mon_unit] ++ z)) @
    amal_omega_H ((x ++ [inl h1, inl h2] ++ y) ++ y0) z) @
   ap amal_eta (app_assoc (x ++ [inl h1, inl h2] ++ y) y0 z)^)
  (fun y0 z : Words =>
   (ap amal_eta
      (app_assoc (x ++ [inl h1, inl h2] ++ y) y0 ([inr mon_unit] ++ z)) @
    amal_omega_K ((x ++ [inl h1, inl h2] ++ y) ++ y0) z) @
   ap amal_eta (app_assoc (x ++ [inl h1, inl h2] ++ y) y0 z)^)
  (amal_eta w) =
amal_type_rec amal_type
  (fun y0 : Words => amal_eta ((x ++ [inl (h1 * h2)] ++ y) ++ y0))
  (fun (y0 z : Words) (h0 h3 : H) =>
   (ap amal_eta
      (app_assoc (x ++ [inl (h1 * h2)] ++ y) y0 ([inl h0, inl h3] ++ z)) @
    amal_mu_H ((x ++ [inl (h1 * h2)] ++ y) ++ y0) z h0 h3) @
   ap amal_eta
     (app_assoc (x ++ [inl (h1 * h2)] ++ y) y0 ([inl (h0 * h3)] ++ z))^)
  (fun (y0 z : Words) (k1 k2 : K) =>
   (ap amal_eta
      (app_assoc (x ++ [inl (h1 * h2)] ++ y) y0 ([inr k1, inr k2] ++ z)) @
    amal_mu_K ((x ++ [inl (h1 * h2)] ++ y) ++ y0) z k1 k2) @
   ap amal_eta
     (app_assoc (x ++ [inl (h1 * h2)] ++ y) y0 ([inr (k1 * k2)] ++ z))^)
  (fun (y0 w0 : Words) (z : G) =>
   (ap amal_eta
      (app_assoc (x ++ [inl (h1 * h2)] ++ y) y0 ([inl (f z)] ++ w0)) @
    amal_tau ((x ++ [inl (h1 * h2)] ++ y) ++ y0) w0 z) @
   ap amal_eta
     (app_assoc (x ++ [inl (h1 * h2)] ++ y) y0 ([inr (g z)] ++ w0))^)
  (fun y0 z : Words =>
   (ap amal_eta
      (app_assoc (x ++ [inl (h1 * h2)] ++ y) y0 ([inl mon_unit] ++ z)) @
    amal_omega_H ((x ++ [inl (h1 * h2)] ++ y) ++ y0) z) @
   ap amal_eta (app_assoc (x ++ [inl (h1 * h2)] ++ y) y0 z)^)
  (fun y0 z : Words =>
   (ap amal_eta
      (app_assoc (x ++ [inl (h1 * h2)] ++ y) y0 ([inr mon_unit] ++ z)) @
    amal_omega_K ((x ++ [inl (h1 * h2)] ++ y) ++ y0) z) @
   ap amal_eta (app_assoc (x ++ [inl (h1 * h2)] ++ y) y0 z)^)
  (amal_eta w)
      intros z;
      change (amal_eta ((x ++ [inl h1, inl h2] ++ y) ++ z)
        = amal_eta ((x ++ [inl (h1 * h2)] ++ y) ++ z)).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
h1, h2: H
z: Words
amal_eta ((x ++ [inl h1, inl h2] ++ y) ++ z) =
amal_eta ((x ++ [inl (h1 * h2)] ++ y) ++ z)
      refine (ap amal_eta _^ @ _ @ ap amal_eta _).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
h1, h2: H
z: Words
?Goal3 = (x ++ [inl h1, inl h2] ++ y) ++ z
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
h1, h2: H
z: Words
amal_eta ?Goal3 = amal_eta ?Goal6
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
h1, h2: H
z: Words
?Goal6 = (x ++ [inl (h1 * h2)] ++ y) ++ z
      1,3: apply app_assoc.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
h1, h2: H
z: Words
amal_eta (x ++ ([inl h1, inl h2] ++ y) ++ z) =
amal_eta (x ++ ([inl (h1 * h2)] ++ y) ++ z)
      refine (ap amal_eta (ap (app x) _)^ @ _ @ ap amal_eta (ap (app x) _)).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
h1, h2: H
z: Words
?Goal3 = ([inl h1, inl h2] ++ y) ++ z
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
h1, h2: H
z: Words
amal_eta (x ++ ?Goal3) = amal_eta (x ++ ?Goal6)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
h1, h2: H
z: Words
?Goal6 = ([inl (h1 * h2)] ++ y) ++ z
      1,3: apply app_assoc.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
h1, h2: H
z: Words
amal_eta (x ++ [inl h1, inl h2] ++ y ++ z) =
amal_eta (x ++ [inl (h1 * h2)] ++ y ++ z)
      apply amal_mu_H. }
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: Words
forall (y : amal_type) (y0 : Words) (k1 k2 : K),
(fun x0 : Words =>
 amal_type_rec amal_type (fun y1 : Words => amal_eta (x0 ++ y1))
   (fun (y1 z : Words) (h1 h2 : H) =>
    (ap amal_eta (app_assoc x0 y1 ([inl h1, inl h2] ++ z)) @
     amal_mu_H (x0 ++ y1) z h1 h2) @
    ap amal_eta (app_assoc x0 y1 ([inl (h1 * h2)] ++ z))^)
   (fun (y1 z : Words) (k0 k3 : K) =>
    (ap amal_eta (app_assoc x0 y1 ([inr k0, inr k3] ++ z)) @
     amal_mu_K (x0 ++ y1) z k0 k3) @
    ap amal_eta (app_assoc x0 y1 ([inr (k0 * k3)] ++ z))^)
   (fun (y1 w : Words) (z : G) =>
    (ap amal_eta (app_assoc x0 y1 ([inl (f z)] ++ w)) @
     amal_tau (x0 ++ y1) w z) @
    ap amal_eta (app_assoc x0 y1 ([inr (g z)] ++ w))^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inl mon_unit] ++ z)) @
     amal_omega_H (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inr mon_unit] ++ z)) @
     amal_omega_K (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   y)
  (x ++ [inr k1, inr k2] ++ y0) =
(fun x0 : Words =>
 amal_type_rec amal_type (fun y1 : Words => amal_eta (x0 ++ y1))
   (fun (y1 z : Words) (h1 h2 : H) =>
    (ap amal_eta (app_assoc x0 y1 ([inl h1, inl h2] ++ z)) @
     amal_mu_H (x0 ++ y1) z h1 h2) @
    ap amal_eta (app_assoc x0 y1 ([inl (h1 * h2)] ++ z))^)
   (fun (y1 z : Words) (k0 k3 : K) =>
    (ap amal_eta (app_assoc x0 y1 ([inr k0, inr k3] ++ z)) @
     amal_mu_K (x0 ++ y1) z k0 k3) @
    ap amal_eta (app_assoc x0 y1 ([inr (k0 * k3)] ++ z))^)
   (fun (y1 w : Words) (z : G) =>
    (ap amal_eta (app_assoc x0 y1 ([inl (f z)] ++ w)) @
     amal_tau (x0 ++ y1) w z) @
    ap amal_eta (app_assoc x0 y1 ([inr (g z)] ++ w))^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inl mon_unit] ++ z)) @
     amal_omega_H (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inr mon_unit] ++ z)) @
     amal_omega_K (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   y)
  (x ++ [inr (k1 * k2)] ++ y0)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: Words
forall (y : amal_type) (y0 : Words) (z : G),
(fun x0 : Words =>
 amal_type_rec amal_type (fun y1 : Words => amal_eta (x0 ++ y1))
   (fun (y1 z0 : Words) (h1 h2 : H) =>
    (ap amal_eta (app_assoc x0 y1 ([inl h1, inl h2] ++ z0)) @
     amal_mu_H (x0 ++ y1) z0 h1 h2) @
    ap amal_eta (app_assoc x0 y1 ([inl (h1 * h2)] ++ z0))^)
   (fun (y1 z0 : Words) (k1 k2 : K) =>
    (ap amal_eta (app_assoc x0 y1 ([inr k1, inr k2] ++ z0)) @
     amal_mu_K (x0 ++ y1) z0 k1 k2) @
    ap amal_eta (app_assoc x0 y1 ([inr (k1 * k2)] ++ z0))^)
   (fun (y1 w : Words) (z0 : G) =>
    (ap amal_eta (app_assoc x0 y1 ([inl (f z0)] ++ w)) @
     amal_tau (x0 ++ y1) w z0) @
    ap amal_eta (app_assoc x0 y1 ([inr (g z0)] ++ w))^)
   (fun y1 z0 : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inl mon_unit] ++ z0)) @
     amal_omega_H (x0 ++ y1) z0) @
    ap amal_eta (app_assoc x0 y1 z0)^)
   (fun y1 z0 : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inr mon_unit] ++ z0)) @
     amal_omega_K (x0 ++ y1) z0) @
    ap amal_eta (app_assoc x0 y1 z0)^)
   y)
  (x ++ [inl (f z)] ++ y0) =
(fun x0 : Words =>
 amal_type_rec amal_type (fun y1 : Words => amal_eta (x0 ++ y1))
   (fun (y1 z0 : Words) (h1 h2 : H) =>
    (ap amal_eta (app_assoc x0 y1 ([inl h1, inl h2] ++ z0)) @
     amal_mu_H (x0 ++ y1) z0 h1 h2) @
    ap amal_eta (app_assoc x0 y1 ([inl (h1 * h2)] ++ z0))^)
   (fun (y1 z0 : Words) (k1 k2 : K) =>
    (ap amal_eta (app_assoc x0 y1 ([inr k1, inr k2] ++ z0)) @
     amal_mu_K (x0 ++ y1) z0 k1 k2) @
    ap amal_eta (app_assoc x0 y1 ([inr (k1 * k2)] ++ z0))^)
   (fun (y1 w : Words) (z0 : G) =>
    (ap amal_eta (app_assoc x0 y1 ([inl (f z0)] ++ w)) @
     amal_tau (x0 ++ y1) w z0) @
    ap amal_eta (app_assoc x0 y1 ([inr (g z0)] ++ w))^)
   (fun y1 z0 : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inl mon_unit] ++ z0)) @
     amal_omega_H (x0 ++ y1) z0) @
    ap amal_eta (app_assoc x0 y1 z0)^)
   (fun y1 z0 : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inr mon_unit] ++ z0)) @
     amal_omega_K (x0 ++ y1) z0) @
    ap amal_eta (app_assoc x0 y1 z0)^)
   y)
  (x ++ [inr (g z)] ++ y0)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: Words
forall (y : amal_type) (y0 : Words),
(fun x0 : Words =>
 amal_type_rec amal_type (fun y1 : Words => amal_eta (x0 ++ y1))
   (fun (y1 z : Words) (h1 h2 : H) =>
    (ap amal_eta (app_assoc x0 y1 ([inl h1, inl h2] ++ z)) @
     amal_mu_H (x0 ++ y1) z h1 h2) @
    ap amal_eta (app_assoc x0 y1 ([inl (h1 * h2)] ++ z))^)
   (fun (y1 z : Words) (k1 k2 : K) =>
    (ap amal_eta (app_assoc x0 y1 ([inr k1, inr k2] ++ z)) @
     amal_mu_K (x0 ++ y1) z k1 k2) @
    ap amal_eta (app_assoc x0 y1 ([inr (k1 * k2)] ++ z))^)
   (fun (y1 w : Words) (z : G) =>
    (ap amal_eta (app_assoc x0 y1 ([inl (f z)] ++ w)) @
     amal_tau (x0 ++ y1) w z) @
    ap amal_eta (app_assoc x0 y1 ([inr (g z)] ++ w))^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inl mon_unit] ++ z)) @
     amal_omega_H (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inr mon_unit] ++ z)) @
     amal_omega_K (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   y)
  (x ++ [inl 1] ++ y0) =
(fun x0 : Words =>
 amal_type_rec amal_type (fun y1 : Words => amal_eta (x0 ++ y1))
   (fun (y1 z : Words) (h1 h2 : H) =>
    (ap amal_eta (app_assoc x0 y1 ([inl h1, inl h2] ++ z)) @
     amal_mu_H (x0 ++ y1) z h1 h2) @
    ap amal_eta (app_assoc x0 y1 ([inl (h1 * h2)] ++ z))^)
   (fun (y1 z : Words) (k1 k2 : K) =>
    (ap amal_eta (app_assoc x0 y1 ([inr k1, inr k2] ++ z)) @
     amal_mu_K (x0 ++ y1) z k1 k2) @
    ap amal_eta (app_assoc x0 y1 ([inr (k1 * k2)] ++ z))^)
   (fun (y1 w : Words) (z : G) =>
    (ap amal_eta (app_assoc x0 y1 ([inl (f z)] ++ w)) @
     amal_tau (x0 ++ y1) w z) @
    ap amal_eta (app_assoc x0 y1 ([inr (g z)] ++ w))^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inl mon_unit] ++ z)) @
     amal_omega_H (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inr mon_unit] ++ z)) @
     amal_omega_K (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   y)
  (x ++ y0)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: Words
forall (y : amal_type) (y0 : Words),
(fun x0 : Words =>
 amal_type_rec amal_type (fun y1 : Words => amal_eta (x0 ++ y1))
   (fun (y1 z : Words) (h1 h2 : H) =>
    (ap amal_eta (app_assoc x0 y1 ([inl h1, inl h2] ++ z)) @
     amal_mu_H (x0 ++ y1) z h1 h2) @
    ap amal_eta (app_assoc x0 y1 ([inl (h1 * h2)] ++ z))^)
   (fun (y1 z : Words) (k1 k2 : K) =>
    (ap amal_eta (app_assoc x0 y1 ([inr k1, inr k2] ++ z)) @
     amal_mu_K (x0 ++ y1) z k1 k2) @
    ap amal_eta (app_assoc x0 y1 ([inr (k1 * k2)] ++ z))^)
   (fun (y1 w : Words) (z : G) =>
    (ap amal_eta (app_assoc x0 y1 ([inl (f z)] ++ w)) @
     amal_tau (x0 ++ y1) w z) @
    ap amal_eta (app_assoc x0 y1 ([inr (g z)] ++ w))^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inl mon_unit] ++ z)) @
     amal_omega_H (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inr mon_unit] ++ z)) @
     amal_omega_K (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   y)
  (x ++ [inr 1] ++ y0) =
(fun x0 : Words =>
 amal_type_rec amal_type (fun y1 : Words => amal_eta (x0 ++ y1))
   (fun (y1 z : Words) (h1 h2 : H) =>
    (ap amal_eta (app_assoc x0 y1 ([inl h1, inl h2] ++ z)) @
     amal_mu_H (x0 ++ y1) z h1 h2) @
    ap amal_eta (app_assoc x0 y1 ([inl (h1 * h2)] ++ z))^)
   (fun (y1 z : Words) (k1 k2 : K) =>
    (ap amal_eta (app_assoc x0 y1 ([inr k1, inr k2] ++ z)) @
     amal_mu_K (x0 ++ y1) z k1 k2) @
    ap amal_eta (app_assoc x0 y1 ([inr (k1 * k2)] ++ z))^)
   (fun (y1 w : Words) (z : G) =>
    (ap amal_eta (app_assoc x0 y1 ([inl (f z)] ++ w)) @
     amal_tau (x0 ++ y1) w z) @
    ap amal_eta (app_assoc x0 y1 ([inr (g z)] ++ w))^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inl mon_unit] ++ z)) @
     amal_omega_H (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inr mon_unit] ++ z)) @
     amal_omega_K (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   y)
  (x ++ y0)
    {
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: Words
forall (y : amal_type) (y0 : Words) (k1 k2 : K),
(fun x0 : Words =>
 amal_type_rec amal_type (fun y1 : Words => amal_eta (x0 ++ y1))
   (fun (y1 z : Words) (h1 h2 : H) =>
    (ap amal_eta (app_assoc x0 y1 ([inl h1, inl h2] ++ z)) @
     amal_mu_H (x0 ++ y1) z h1 h2) @
    ap amal_eta (app_assoc x0 y1 ([inl (h1 * h2)] ++ z))^)
   (fun (y1 z : Words) (k0 k3 : K) =>
    (ap amal_eta (app_assoc x0 y1 ([inr k0, inr k3] ++ z)) @
     amal_mu_K (x0 ++ y1) z k0 k3) @
    ap amal_eta (app_assoc x0 y1 ([inr (k0 * k3)] ++ z))^)
   (fun (y1 w : Words) (z : G) =>
    (ap amal_eta (app_assoc x0 y1 ([inl (f z)] ++ w)) @
     amal_tau (x0 ++ y1) w z) @
    ap amal_eta (app_assoc x0 y1 ([inr (g z)] ++ w))^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inl mon_unit] ++ z)) @
     amal_omega_H (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inr mon_unit] ++ z)) @
     amal_omega_K (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   y)
  (x ++ [inr k1, inr k2] ++ y0) =
(fun x0 : Words =>
 amal_type_rec amal_type (fun y1 : Words => amal_eta (x0 ++ y1))
   (fun (y1 z : Words) (h1 h2 : H) =>
    (ap amal_eta (app_assoc x0 y1 ([inl h1, inl h2] ++ z)) @
     amal_mu_H (x0 ++ y1) z h1 h2) @
    ap amal_eta (app_assoc x0 y1 ([inl (h1 * h2)] ++ z))^)
   (fun (y1 z : Words) (k0 k3 : K) =>
    (ap amal_eta (app_assoc x0 y1 ([inr k0, inr k3] ++ z)) @
     amal_mu_K (x0 ++ y1) z k0 k3) @
    ap amal_eta (app_assoc x0 y1 ([inr (k0 * k3)] ++ z))^)
   (fun (y1 w : Words) (z : G) =>
    (ap amal_eta (app_assoc x0 y1 ([inl (f z)] ++ w)) @
     amal_tau (x0 ++ y1) w z) @
    ap amal_eta (app_assoc x0 y1 ([inr (g z)] ++ w))^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inl mon_unit] ++ z)) @
     amal_omega_H (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inr mon_unit] ++ z)) @
     amal_omega_K (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   y)
  (x ++ [inr (k1 * k2)] ++ y0) intros r y k1 k2; revert r.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
k1, k2: K
forall r : amal_type,
(fun x0 : Words =>
 amal_type_rec amal_type (fun y0 : Words => amal_eta (x0 ++ y0))
   (fun (y0 z : Words) (h1 h2 : H) =>
    (ap amal_eta (app_assoc x0 y0 ([inl h1, inl h2] ++ z)) @
     amal_mu_H (x0 ++ y0) z h1 h2) @
    ap amal_eta (app_assoc x0 y0 ([inl (h1 * h2)] ++ z))^)
   (fun (y0 z : Words) (k0 k3 : K) =>
    (ap amal_eta (app_assoc x0 y0 ([inr k0, inr k3] ++ z)) @
     amal_mu_K (x0 ++ y0) z k0 k3) @
    ap amal_eta (app_assoc x0 y0 ([inr (k0 * k3)] ++ z))^)
   (fun (y0 w : Words) (z : G) =>
    (ap amal_eta (app_assoc x0 y0 ([inl (f z)] ++ w)) @
     amal_tau (x0 ++ y0) w z) @
    ap amal_eta (app_assoc x0 y0 ([inr (g z)] ++ w))^)
   (fun y0 z : Words =>
    (ap amal_eta (app_assoc x0 y0 ([inl mon_unit] ++ z)) @
     amal_omega_H (x0 ++ y0) z) @
    ap amal_eta (app_assoc x0 y0 z)^)
   (fun y0 z : Words =>
    (ap amal_eta (app_assoc x0 y0 ([inr mon_unit] ++ z)) @
     amal_omega_K (x0 ++ y0) z) @
    ap amal_eta (app_assoc x0 y0 z)^)
   r)
  (x ++ [inr k1, inr k2] ++ y) =
(fun x0 : Words =>
 amal_type_rec amal_type (fun y0 : Words => amal_eta (x0 ++ y0))
   (fun (y0 z : Words) (h1 h2 : H) =>
    (ap amal_eta (app_assoc x0 y0 ([inl h1, inl h2] ++ z)) @
     amal_mu_H (x0 ++ y0) z h1 h2) @
    ap amal_eta (app_assoc x0 y0 ([inl (h1 * h2)] ++ z))^)
   (fun (y0 z : Words) (k0 k3 : K) =>
    (ap amal_eta (app_assoc x0 y0 ([inr k0, inr k3] ++ z)) @
     amal_mu_K (x0 ++ y0) z k0 k3) @
    ap amal_eta (app_assoc x0 y0 ([inr (k0 * k3)] ++ z))^)
   (fun (y0 w : Words) (z : G) =>
    (ap amal_eta (app_assoc x0 y0 ([inl (f z)] ++ w)) @
     amal_tau (x0 ++ y0) w z) @
    ap amal_eta (app_assoc x0 y0 ([inr (g z)] ++ w))^)
   (fun y0 z : Words =>
    (ap amal_eta (app_assoc x0 y0 ([inl mon_unit] ++ z)) @
     amal_omega_H (x0 ++ y0) z) @
    ap amal_eta (app_assoc x0 y0 z)^)
   (fun y0 z : Words =>
    (ap amal_eta (app_assoc x0 y0 ([inr mon_unit] ++ z)) @
     amal_omega_K (x0 ++ y0) z) @
    ap amal_eta (app_assoc x0 y0 z)^)
   r)
  (x ++ [inr (k1 * k2)] ++ y)
      rapply amal_type_ind_hprop.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
k1, k2: K
forall w : Words,
amal_type_rec amal_type
  (fun y0 : Words => amal_eta ((x ++ [inr k1, inr k2] ++ y) ++ y0))
  (fun (y0 z : Words) (h1 h2 : H) =>
   (ap amal_eta
      (app_assoc (x ++ [inr k1, inr k2] ++ y) y0 ([inl h1, inl h2] ++ z)) @
    amal_mu_H ((x ++ [inr k1, inr k2] ++ y) ++ y0) z h1 h2) @
   ap amal_eta
     (app_assoc (x ++ [inr k1, inr k2] ++ y) y0 ([inl (h1 * h2)] ++ z))^)
  (fun (y0 z : Words) (k0 k3 : K) =>
   (ap amal_eta
      (app_assoc (x ++ [inr k1, inr k2] ++ y) y0 ([inr k0, inr k3] ++ z)) @
    amal_mu_K ((x ++ [inr k1, inr k2] ++ y) ++ y0) z k0 k3) @
   ap amal_eta
     (app_assoc (x ++ [inr k1, inr k2] ++ y) y0 ([inr (k0 * k3)] ++ z))^)
  (fun (y0 w0 : Words) (z : G) =>
   (ap amal_eta
      (app_assoc (x ++ [inr k1, inr k2] ++ y) y0 ([inl (f z)] ++ w0)) @
    amal_tau ((x ++ [inr k1, inr k2] ++ y) ++ y0) w0 z) @
   ap amal_eta
     (app_assoc (x ++ [inr k1, inr k2] ++ y) y0 ([inr (g z)] ++ w0))^)
  (fun y0 z : Words =>
   (ap amal_eta
      (app_assoc (x ++ [inr k1, inr k2] ++ y) y0 ([inl mon_unit] ++ z)) @
    amal_omega_H ((x ++ [inr k1, inr k2] ++ y) ++ y0) z) @
   ap amal_eta (app_assoc (x ++ [inr k1, inr k2] ++ y) y0 z)^)
  (fun y0 z : Words =>
   (ap amal_eta
      (app_assoc (x ++ [inr k1, inr k2] ++ y) y0 ([inr mon_unit] ++ z)) @
    amal_omega_K ((x ++ [inr k1, inr k2] ++ y) ++ y0) z) @
   ap amal_eta (app_assoc (x ++ [inr k1, inr k2] ++ y) y0 z)^)
  (amal_eta w) =
amal_type_rec amal_type
  (fun y0 : Words => amal_eta ((x ++ [inr (k1 * k2)] ++ y) ++ y0))
  (fun (y0 z : Words) (h1 h2 : H) =>
   (ap amal_eta
      (app_assoc (x ++ [inr (k1 * k2)] ++ y) y0 ([inl h1, inl h2] ++ z)) @
    amal_mu_H ((x ++ [inr (k1 * k2)] ++ y) ++ y0) z h1 h2) @
   ap amal_eta
     (app_assoc (x ++ [inr (k1 * k2)] ++ y) y0 ([inl (h1 * h2)] ++ z))^)
  (fun (y0 z : Words) (k0 k3 : K) =>
   (ap amal_eta
      (app_assoc (x ++ [inr (k1 * k2)] ++ y) y0 ([inr k0, inr k3] ++ z)) @
    amal_mu_K ((x ++ [inr (k1 * k2)] ++ y) ++ y0) z k0 k3) @
   ap amal_eta
     (app_assoc (x ++ [inr (k1 * k2)] ++ y) y0 ([inr (k0 * k3)] ++ z))^)
  (fun (y0 w0 : Words) (z : G) =>
   (ap amal_eta
      (app_assoc (x ++ [inr (k1 * k2)] ++ y) y0 ([inl (f z)] ++ w0)) @
    amal_tau ((x ++ [inr (k1 * k2)] ++ y) ++ y0) w0 z) @
   ap amal_eta
     (app_assoc (x ++ [inr (k1 * k2)] ++ y) y0 ([inr (g z)] ++ w0))^)
  (fun y0 z : Words =>
   (ap amal_eta
      (app_assoc (x ++ [inr (k1 * k2)] ++ y) y0 ([inl mon_unit] ++ z)) @
    amal_omega_H ((x ++ [inr (k1 * k2)] ++ y) ++ y0) z) @
   ap amal_eta (app_assoc (x ++ [inr (k1 * k2)] ++ y) y0 z)^)
  (fun y0 z : Words =>
   (ap amal_eta
      (app_assoc (x ++ [inr (k1 * k2)] ++ y) y0 ([inr mon_unit] ++ z)) @
    amal_omega_K ((x ++ [inr (k1 * k2)] ++ y) ++ y0) z) @
   ap amal_eta (app_assoc (x ++ [inr (k1 * k2)] ++ y) y0 z)^)
  (amal_eta w)
      intros z;
      change (amal_eta ((x ++ [inr k1, inr k2] ++ y) ++ z)
        = amal_eta ((x ++ [inr (k1 * k2)] ++ y) ++ z)).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
k1, k2: K
z: Words
amal_eta ((x ++ [inr k1, inr k2] ++ y) ++ z) =
amal_eta ((x ++ [inr (k1 * k2)] ++ y) ++ z)
      refine (ap amal_eta _^ @ _ @ ap amal_eta _).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
k1, k2: K
z: Words
?Goal2 = (x ++ [inr k1, inr k2] ++ y) ++ z
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
k1, k2: K
z: Words
amal_eta ?Goal2 = amal_eta ?Goal5
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
k1, k2: K
z: Words
?Goal5 = (x ++ [inr (k1 * k2)] ++ y) ++ z
      1,3: apply app_assoc.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
k1, k2: K
z: Words
amal_eta (x ++ ([inr k1, inr k2] ++ y) ++ z) =
amal_eta (x ++ ([inr (k1 * k2)] ++ y) ++ z)
      refine (ap amal_eta (ap (app x) _)^ @ _ @ ap amal_eta (ap (app x) _)).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
k1, k2: K
z: Words
?Goal2 = ([inr k1, inr k2] ++ y) ++ z
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
k1, k2: K
z: Words
amal_eta (x ++ ?Goal2) = amal_eta (x ++ ?Goal5)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
k1, k2: K
z: Words
?Goal5 = ([inr (k1 * k2)] ++ y) ++ z
      1,3: apply app_assoc.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
k1, k2: K
z: Words
amal_eta (x ++ [inr k1, inr k2] ++ y ++ z) =
amal_eta (x ++ [inr (k1 * k2)] ++ y ++ z)
      apply amal_mu_K. }
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: Words
forall (y : amal_type) (y0 : Words) (z : G),
(fun x0 : Words =>
 amal_type_rec amal_type (fun y1 : Words => amal_eta (x0 ++ y1))
   (fun (y1 z0 : Words) (h1 h2 : H) =>
    (ap amal_eta (app_assoc x0 y1 ([inl h1, inl h2] ++ z0)) @
     amal_mu_H (x0 ++ y1) z0 h1 h2) @
    ap amal_eta (app_assoc x0 y1 ([inl (h1 * h2)] ++ z0))^)
   (fun (y1 z0 : Words) (k1 k2 : K) =>
    (ap amal_eta (app_assoc x0 y1 ([inr k1, inr k2] ++ z0)) @
     amal_mu_K (x0 ++ y1) z0 k1 k2) @
    ap amal_eta (app_assoc x0 y1 ([inr (k1 * k2)] ++ z0))^)
   (fun (y1 w : Words) (z0 : G) =>
    (ap amal_eta (app_assoc x0 y1 ([inl (f z0)] ++ w)) @
     amal_tau (x0 ++ y1) w z0) @
    ap amal_eta (app_assoc x0 y1 ([inr (g z0)] ++ w))^)
   (fun y1 z0 : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inl mon_unit] ++ z0)) @
     amal_omega_H (x0 ++ y1) z0) @
    ap amal_eta (app_assoc x0 y1 z0)^)
   (fun y1 z0 : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inr mon_unit] ++ z0)) @
     amal_omega_K (x0 ++ y1) z0) @
    ap amal_eta (app_assoc x0 y1 z0)^)
   y)
  (x ++ [inl (f z)] ++ y0) =
(fun x0 : Words =>
 amal_type_rec amal_type (fun y1 : Words => amal_eta (x0 ++ y1))
   (fun (y1 z0 : Words) (h1 h2 : H) =>
    (ap amal_eta (app_assoc x0 y1 ([inl h1, inl h2] ++ z0)) @
     amal_mu_H (x0 ++ y1) z0 h1 h2) @
    ap amal_eta (app_assoc x0 y1 ([inl (h1 * h2)] ++ z0))^)
   (fun (y1 z0 : Words) (k1 k2 : K) =>
    (ap amal_eta (app_assoc x0 y1 ([inr k1, inr k2] ++ z0)) @
     amal_mu_K (x0 ++ y1) z0 k1 k2) @
    ap amal_eta (app_assoc x0 y1 ([inr (k1 * k2)] ++ z0))^)
   (fun (y1 w : Words) (z0 : G) =>
    (ap amal_eta (app_assoc x0 y1 ([inl (f z0)] ++ w)) @
     amal_tau (x0 ++ y1) w z0) @
    ap amal_eta (app_assoc x0 y1 ([inr (g z0)] ++ w))^)
   (fun y1 z0 : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inl mon_unit] ++ z0)) @
     amal_omega_H (x0 ++ y1) z0) @
    ap amal_eta (app_assoc x0 y1 z0)^)
   (fun y1 z0 : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inr mon_unit] ++ z0)) @
     amal_omega_K (x0 ++ y1) z0) @
    ap amal_eta (app_assoc x0 y1 z0)^)
   y)
  (x ++ [inr (g z)] ++ y0)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: Words
forall (y : amal_type) (y0 : Words),
(fun x0 : Words =>
 amal_type_rec amal_type (fun y1 : Words => amal_eta (x0 ++ y1))
   (fun (y1 z : Words) (h1 h2 : H) =>
    (ap amal_eta (app_assoc x0 y1 ([inl h1, inl h2] ++ z)) @
     amal_mu_H (x0 ++ y1) z h1 h2) @
    ap amal_eta (app_assoc x0 y1 ([inl (h1 * h2)] ++ z))^)
   (fun (y1 z : Words) (k1 k2 : K) =>
    (ap amal_eta (app_assoc x0 y1 ([inr k1, inr k2] ++ z)) @
     amal_mu_K (x0 ++ y1) z k1 k2) @
    ap amal_eta (app_assoc x0 y1 ([inr (k1 * k2)] ++ z))^)
   (fun (y1 w : Words) (z : G) =>
    (ap amal_eta (app_assoc x0 y1 ([inl (f z)] ++ w)) @
     amal_tau (x0 ++ y1) w z) @
    ap amal_eta (app_assoc x0 y1 ([inr (g z)] ++ w))^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inl mon_unit] ++ z)) @
     amal_omega_H (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inr mon_unit] ++ z)) @
     amal_omega_K (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   y)
  (x ++ [inl 1] ++ y0) =
(fun x0 : Words =>
 amal_type_rec amal_type (fun y1 : Words => amal_eta (x0 ++ y1))
   (fun (y1 z : Words) (h1 h2 : H) =>
    (ap amal_eta (app_assoc x0 y1 ([inl h1, inl h2] ++ z)) @
     amal_mu_H (x0 ++ y1) z h1 h2) @
    ap amal_eta (app_assoc x0 y1 ([inl (h1 * h2)] ++ z))^)
   (fun (y1 z : Words) (k1 k2 : K) =>
    (ap amal_eta (app_assoc x0 y1 ([inr k1, inr k2] ++ z)) @
     amal_mu_K (x0 ++ y1) z k1 k2) @
    ap amal_eta (app_assoc x0 y1 ([inr (k1 * k2)] ++ z))^)
   (fun (y1 w : Words) (z : G) =>
    (ap amal_eta (app_assoc x0 y1 ([inl (f z)] ++ w)) @
     amal_tau (x0 ++ y1) w z) @
    ap amal_eta (app_assoc x0 y1 ([inr (g z)] ++ w))^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inl mon_unit] ++ z)) @
     amal_omega_H (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inr mon_unit] ++ z)) @
     amal_omega_K (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   y)
  (x ++ y0)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: Words
forall (y : amal_type) (y0 : Words),
(fun x0 : Words =>
 amal_type_rec amal_type (fun y1 : Words => amal_eta (x0 ++ y1))
   (fun (y1 z : Words) (h1 h2 : H) =>
    (ap amal_eta (app_assoc x0 y1 ([inl h1, inl h2] ++ z)) @
     amal_mu_H (x0 ++ y1) z h1 h2) @
    ap amal_eta (app_assoc x0 y1 ([inl (h1 * h2)] ++ z))^)
   (fun (y1 z : Words) (k1 k2 : K) =>
    (ap amal_eta (app_assoc x0 y1 ([inr k1, inr k2] ++ z)) @
     amal_mu_K (x0 ++ y1) z k1 k2) @
    ap amal_eta (app_assoc x0 y1 ([inr (k1 * k2)] ++ z))^)
   (fun (y1 w : Words) (z : G) =>
    (ap amal_eta (app_assoc x0 y1 ([inl (f z)] ++ w)) @
     amal_tau (x0 ++ y1) w z) @
    ap amal_eta (app_assoc x0 y1 ([inr (g z)] ++ w))^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inl mon_unit] ++ z)) @
     amal_omega_H (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inr mon_unit] ++ z)) @
     amal_omega_K (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   y)
  (x ++ [inr 1] ++ y0) =
(fun x0 : Words =>
 amal_type_rec amal_type (fun y1 : Words => amal_eta (x0 ++ y1))
   (fun (y1 z : Words) (h1 h2 : H) =>
    (ap amal_eta (app_assoc x0 y1 ([inl h1, inl h2] ++ z)) @
     amal_mu_H (x0 ++ y1) z h1 h2) @
    ap amal_eta (app_assoc x0 y1 ([inl (h1 * h2)] ++ z))^)
   (fun (y1 z : Words) (k1 k2 : K) =>
    (ap amal_eta (app_assoc x0 y1 ([inr k1, inr k2] ++ z)) @
     amal_mu_K (x0 ++ y1) z k1 k2) @
    ap amal_eta (app_assoc x0 y1 ([inr (k1 * k2)] ++ z))^)
   (fun (y1 w : Words) (z : G) =>
    (ap amal_eta (app_assoc x0 y1 ([inl (f z)] ++ w)) @
     amal_tau (x0 ++ y1) w z) @
    ap amal_eta (app_assoc x0 y1 ([inr (g z)] ++ w))^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inl mon_unit] ++ z)) @
     amal_omega_H (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inr mon_unit] ++ z)) @
     amal_omega_K (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   y)
  (x ++ y0)
    {
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: Words
forall (y : amal_type) (y0 : Words) (z : G),
(fun x0 : Words =>
 amal_type_rec amal_type (fun y1 : Words => amal_eta (x0 ++ y1))
   (fun (y1 z0 : Words) (h1 h2 : H) =>
    (ap amal_eta (app_assoc x0 y1 ([inl h1, inl h2] ++ z0)) @
     amal_mu_H (x0 ++ y1) z0 h1 h2) @
    ap amal_eta (app_assoc x0 y1 ([inl (h1 * h2)] ++ z0))^)
   (fun (y1 z0 : Words) (k1 k2 : K) =>
    (ap amal_eta (app_assoc x0 y1 ([inr k1, inr k2] ++ z0)) @
     amal_mu_K (x0 ++ y1) z0 k1 k2) @
    ap amal_eta (app_assoc x0 y1 ([inr (k1 * k2)] ++ z0))^)
   (fun (y1 w : Words) (z0 : G) =>
    (ap amal_eta (app_assoc x0 y1 ([inl (f z0)] ++ w)) @
     amal_tau (x0 ++ y1) w z0) @
    ap amal_eta (app_assoc x0 y1 ([inr (g z0)] ++ w))^)
   (fun y1 z0 : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inl mon_unit] ++ z0)) @
     amal_omega_H (x0 ++ y1) z0) @
    ap amal_eta (app_assoc x0 y1 z0)^)
   (fun y1 z0 : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inr mon_unit] ++ z0)) @
     amal_omega_K (x0 ++ y1) z0) @
    ap amal_eta (app_assoc x0 y1 z0)^)
   y)
  (x ++ [inl (f z)] ++ y0) =
(fun x0 : Words =>
 amal_type_rec amal_type (fun y1 : Words => amal_eta (x0 ++ y1))
   (fun (y1 z0 : Words) (h1 h2 : H) =>
    (ap amal_eta (app_assoc x0 y1 ([inl h1, inl h2] ++ z0)) @
     amal_mu_H (x0 ++ y1) z0 h1 h2) @
    ap amal_eta (app_assoc x0 y1 ([inl (h1 * h2)] ++ z0))^)
   (fun (y1 z0 : Words) (k1 k2 : K) =>
    (ap amal_eta (app_assoc x0 y1 ([inr k1, inr k2] ++ z0)) @
     amal_mu_K (x0 ++ y1) z0 k1 k2) @
    ap amal_eta (app_assoc x0 y1 ([inr (k1 * k2)] ++ z0))^)
   (fun (y1 w : Words) (z0 : G) =>
    (ap amal_eta (app_assoc x0 y1 ([inl (f z0)] ++ w)) @
     amal_tau (x0 ++ y1) w z0) @
    ap amal_eta (app_assoc x0 y1 ([inr (g z0)] ++ w))^)
   (fun y1 z0 : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inl mon_unit] ++ z0)) @
     amal_omega_H (x0 ++ y1) z0) @
    ap amal_eta (app_assoc x0 y1 z0)^)
   (fun y1 z0 : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inr mon_unit] ++ z0)) @
     amal_omega_K (x0 ++ y1) z0) @
    ap amal_eta (app_assoc x0 y1 z0)^)
   y)
  (x ++ [inr (g z)] ++ y0) intros r y z; revert r.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
z: G
forall r : amal_type,
(fun x0 : Words =>
 amal_type_rec amal_type (fun y0 : Words => amal_eta (x0 ++ y0))
   (fun (y0 z0 : Words) (h1 h2 : H) =>
    (ap amal_eta (app_assoc x0 y0 ([inl h1, inl h2] ++ z0)) @
     amal_mu_H (x0 ++ y0) z0 h1 h2) @
    ap amal_eta (app_assoc x0 y0 ([inl (h1 * h2)] ++ z0))^)
   (fun (y0 z0 : Words) (k1 k2 : K) =>
    (ap amal_eta (app_assoc x0 y0 ([inr k1, inr k2] ++ z0)) @
     amal_mu_K (x0 ++ y0) z0 k1 k2) @
    ap amal_eta (app_assoc x0 y0 ([inr (k1 * k2)] ++ z0))^)
   (fun (y0 w : Words) (z0 : G) =>
    (ap amal_eta (app_assoc x0 y0 ([inl (f z0)] ++ w)) @
     amal_tau (x0 ++ y0) w z0) @
    ap amal_eta (app_assoc x0 y0 ([inr (g z0)] ++ w))^)
   (fun y0 z0 : Words =>
    (ap amal_eta (app_assoc x0 y0 ([inl mon_unit] ++ z0)) @
     amal_omega_H (x0 ++ y0) z0) @
    ap amal_eta (app_assoc x0 y0 z0)^)
   (fun y0 z0 : Words =>
    (ap amal_eta (app_assoc x0 y0 ([inr mon_unit] ++ z0)) @
     amal_omega_K (x0 ++ y0) z0) @
    ap amal_eta (app_assoc x0 y0 z0)^)
   r)
  (x ++ [inl (f z)] ++ y) =
(fun x0 : Words =>
 amal_type_rec amal_type (fun y0 : Words => amal_eta (x0 ++ y0))
   (fun (y0 z0 : Words) (h1 h2 : H) =>
    (ap amal_eta (app_assoc x0 y0 ([inl h1, inl h2] ++ z0)) @
     amal_mu_H (x0 ++ y0) z0 h1 h2) @
    ap amal_eta (app_assoc x0 y0 ([inl (h1 * h2)] ++ z0))^)
   (fun (y0 z0 : Words) (k1 k2 : K) =>
    (ap amal_eta (app_assoc x0 y0 ([inr k1, inr k2] ++ z0)) @
     amal_mu_K (x0 ++ y0) z0 k1 k2) @
    ap amal_eta (app_assoc x0 y0 ([inr (k1 * k2)] ++ z0))^)
   (fun (y0 w : Words) (z0 : G) =>
    (ap amal_eta (app_assoc x0 y0 ([inl (f z0)] ++ w)) @
     amal_tau (x0 ++ y0) w z0) @
    ap amal_eta (app_assoc x0 y0 ([inr (g z0)] ++ w))^)
   (fun y0 z0 : Words =>
    (ap amal_eta (app_assoc x0 y0 ([inl mon_unit] ++ z0)) @
     amal_omega_H (x0 ++ y0) z0) @
    ap amal_eta (app_assoc x0 y0 z0)^)
   (fun y0 z0 : Words =>
    (ap amal_eta (app_assoc x0 y0 ([inr mon_unit] ++ z0)) @
     amal_omega_K (x0 ++ y0) z0) @
    ap amal_eta (app_assoc x0 y0 z0)^)
   r)
  (x ++ [inr (g z)] ++ y)
      rapply amal_type_ind_hprop.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
z: G
forall w : Words,
amal_type_rec amal_type
  (fun y0 : Words => amal_eta ((x ++ [inl (f z)] ++ y) ++ y0))
  (fun (y0 z0 : Words) (h1 h2 : H) =>
   (ap amal_eta
      (app_assoc (x ++ [inl (f z)] ++ y) y0 ([inl h1, inl h2] ++ z0)) @
    amal_mu_H ((x ++ [inl (f z)] ++ y) ++ y0) z0 h1 h2) @
   ap amal_eta
     (app_assoc (x ++ [inl (f z)] ++ y) y0 ([inl (h1 * h2)] ++ z0))^)
  (fun (y0 z0 : Words) (k1 k2 : K) =>
   (ap amal_eta
      (app_assoc (x ++ [inl (f z)] ++ y) y0 ([inr k1, inr k2] ++ z0)) @
    amal_mu_K ((x ++ [inl (f z)] ++ y) ++ y0) z0 k1 k2) @
   ap amal_eta
     (app_assoc (x ++ [inl (f z)] ++ y) y0 ([inr (k1 * k2)] ++ z0))^)
  (fun (y0 w0 : Words) (z0 : G) =>
   (ap amal_eta (app_assoc (x ++ [inl (f z)] ++ y) y0 ([inl (f z0)] ++ w0)) @
    amal_tau ((x ++ [inl (f z)] ++ y) ++ y0) w0 z0) @
   ap amal_eta (app_assoc (x ++ [inl (f z)] ++ y) y0 ([inr (g z0)] ++ w0))^)
  (fun y0 z0 : Words =>
   (ap amal_eta (app_assoc (x ++ [inl (f z)] ++ y) y0 ([inl mon_unit] ++ z0)) @
    amal_omega_H ((x ++ [inl (f z)] ++ y) ++ y0) z0) @
   ap amal_eta (app_assoc (x ++ [inl (f z)] ++ y) y0 z0)^)
  (fun y0 z0 : Words =>
   (ap amal_eta (app_assoc (x ++ [inl (f z)] ++ y) y0 ([inr mon_unit] ++ z0)) @
    amal_omega_K ((x ++ [inl (f z)] ++ y) ++ y0) z0) @
   ap amal_eta (app_assoc (x ++ [inl (f z)] ++ y) y0 z0)^)
  (amal_eta w) =
amal_type_rec amal_type
  (fun y0 : Words => amal_eta ((x ++ [inr (g z)] ++ y) ++ y0))
  (fun (y0 z0 : Words) (h1 h2 : H) =>
   (ap amal_eta
      (app_assoc (x ++ [inr (g z)] ++ y) y0 ([inl h1, inl h2] ++ z0)) @
    amal_mu_H ((x ++ [inr (g z)] ++ y) ++ y0) z0 h1 h2) @
   ap amal_eta
     (app_assoc (x ++ [inr (g z)] ++ y) y0 ([inl (h1 * h2)] ++ z0))^)
  (fun (y0 z0 : Words) (k1 k2 : K) =>
   (ap amal_eta
      (app_assoc (x ++ [inr (g z)] ++ y) y0 ([inr k1, inr k2] ++ z0)) @
    amal_mu_K ((x ++ [inr (g z)] ++ y) ++ y0) z0 k1 k2) @
   ap amal_eta
     (app_assoc (x ++ [inr (g z)] ++ y) y0 ([inr (k1 * k2)] ++ z0))^)
  (fun (y0 w0 : Words) (z0 : G) =>
   (ap amal_eta (app_assoc (x ++ [inr (g z)] ++ y) y0 ([inl (f z0)] ++ w0)) @
    amal_tau ((x ++ [inr (g z)] ++ y) ++ y0) w0 z0) @
   ap amal_eta (app_assoc (x ++ [inr (g z)] ++ y) y0 ([inr (g z0)] ++ w0))^)
  (fun y0 z0 : Words =>
   (ap amal_eta (app_assoc (x ++ [inr (g z)] ++ y) y0 ([inl mon_unit] ++ z0)) @
    amal_omega_H ((x ++ [inr (g z)] ++ y) ++ y0) z0) @
   ap amal_eta (app_assoc (x ++ [inr (g z)] ++ y) y0 z0)^)
  (fun y0 z0 : Words =>
   (ap amal_eta (app_assoc (x ++ [inr (g z)] ++ y) y0 ([inr mon_unit] ++ z0)) @
    amal_omega_K ((x ++ [inr (g z)] ++ y) ++ y0) z0) @
   ap amal_eta (app_assoc (x ++ [inr (g z)] ++ y) y0 z0)^)
  (amal_eta w)
      intros w;
      change (amal_eta ((x ++ [inl (f z)] ++ y) ++ w)
        = amal_eta ((x ++ [inr (g z)] ++ y) ++ w)).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
z: G
w: Words
amal_eta ((x ++ [inl (f z)] ++ y) ++ w) =
amal_eta ((x ++ [inr (g z)] ++ y) ++ w)
      refine (ap amal_eta _^ @ _ @ ap amal_eta _).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
z: G
w: Words
?Goal1 = (x ++ [inl (f z)] ++ y) ++ w
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
z: G
w: Words
amal_eta ?Goal1 = amal_eta ?Goal4
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
z: G
w: Words
?Goal4 = (x ++ [inr (g z)] ++ y) ++ w
      1,3: apply app_assoc.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
z: G
w: Words
amal_eta (x ++ ([inl (f z)] ++ y) ++ w) =
amal_eta (x ++ ([inr (g z)] ++ y) ++ w)
      refine (ap amal_eta (ap (app x) _)^ @ _ @ ap amal_eta (ap (app x) _)).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
z: G
w: Words
?Goal1 = ([inl (f z)] ++ y) ++ w
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
z: G
w: Words
amal_eta (x ++ ?Goal1) = amal_eta (x ++ ?Goal4)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
z: G
w: Words
?Goal4 = ([inr (g z)] ++ y) ++ w
      1,3: apply app_assoc.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
z: G
w: Words
amal_eta (x ++ [inl (f z)] ++ y ++ w) = amal_eta (x ++ [inr (g z)] ++ y ++ w)
      apply amal_tau. }
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: Words
forall (y : amal_type) (y0 : Words),
(fun x0 : Words =>
 amal_type_rec amal_type (fun y1 : Words => amal_eta (x0 ++ y1))
   (fun (y1 z : Words) (h1 h2 : H) =>
    (ap amal_eta (app_assoc x0 y1 ([inl h1, inl h2] ++ z)) @
     amal_mu_H (x0 ++ y1) z h1 h2) @
    ap amal_eta (app_assoc x0 y1 ([inl (h1 * h2)] ++ z))^)
   (fun (y1 z : Words) (k1 k2 : K) =>
    (ap amal_eta (app_assoc x0 y1 ([inr k1, inr k2] ++ z)) @
     amal_mu_K (x0 ++ y1) z k1 k2) @
    ap amal_eta (app_assoc x0 y1 ([inr (k1 * k2)] ++ z))^)
   (fun (y1 w : Words) (z : G) =>
    (ap amal_eta (app_assoc x0 y1 ([inl (f z)] ++ w)) @
     amal_tau (x0 ++ y1) w z) @
    ap amal_eta (app_assoc x0 y1 ([inr (g z)] ++ w))^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inl mon_unit] ++ z)) @
     amal_omega_H (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inr mon_unit] ++ z)) @
     amal_omega_K (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   y)
  (x ++ [inl 1] ++ y0) =
(fun x0 : Words =>
 amal_type_rec amal_type (fun y1 : Words => amal_eta (x0 ++ y1))
   (fun (y1 z : Words) (h1 h2 : H) =>
    (ap amal_eta (app_assoc x0 y1 ([inl h1, inl h2] ++ z)) @
     amal_mu_H (x0 ++ y1) z h1 h2) @
    ap amal_eta (app_assoc x0 y1 ([inl (h1 * h2)] ++ z))^)
   (fun (y1 z : Words) (k1 k2 : K) =>
    (ap amal_eta (app_assoc x0 y1 ([inr k1, inr k2] ++ z)) @
     amal_mu_K (x0 ++ y1) z k1 k2) @
    ap amal_eta (app_assoc x0 y1 ([inr (k1 * k2)] ++ z))^)
   (fun (y1 w : Words) (z : G) =>
    (ap amal_eta (app_assoc x0 y1 ([inl (f z)] ++ w)) @
     amal_tau (x0 ++ y1) w z) @
    ap amal_eta (app_assoc x0 y1 ([inr (g z)] ++ w))^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inl mon_unit] ++ z)) @
     amal_omega_H (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inr mon_unit] ++ z)) @
     amal_omega_K (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   y)
  (x ++ y0)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: Words
forall (y : amal_type) (y0 : Words),
(fun x0 : Words =>
 amal_type_rec amal_type (fun y1 : Words => amal_eta (x0 ++ y1))
   (fun (y1 z : Words) (h1 h2 : H) =>
    (ap amal_eta (app_assoc x0 y1 ([inl h1, inl h2] ++ z)) @
     amal_mu_H (x0 ++ y1) z h1 h2) @
    ap amal_eta (app_assoc x0 y1 ([inl (h1 * h2)] ++ z))^)
   (fun (y1 z : Words) (k1 k2 : K) =>
    (ap amal_eta (app_assoc x0 y1 ([inr k1, inr k2] ++ z)) @
     amal_mu_K (x0 ++ y1) z k1 k2) @
    ap amal_eta (app_assoc x0 y1 ([inr (k1 * k2)] ++ z))^)
   (fun (y1 w : Words) (z : G) =>
    (ap amal_eta (app_assoc x0 y1 ([inl (f z)] ++ w)) @
     amal_tau (x0 ++ y1) w z) @
    ap amal_eta (app_assoc x0 y1 ([inr (g z)] ++ w))^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inl mon_unit] ++ z)) @
     amal_omega_H (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inr mon_unit] ++ z)) @
     amal_omega_K (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   y)
  (x ++ [inr 1] ++ y0) =
(fun x0 : Words =>
 amal_type_rec amal_type (fun y1 : Words => amal_eta (x0 ++ y1))
   (fun (y1 z : Words) (h1 h2 : H) =>
    (ap amal_eta (app_assoc x0 y1 ([inl h1, inl h2] ++ z)) @
     amal_mu_H (x0 ++ y1) z h1 h2) @
    ap amal_eta (app_assoc x0 y1 ([inl (h1 * h2)] ++ z))^)
   (fun (y1 z : Words) (k1 k2 : K) =>
    (ap amal_eta (app_assoc x0 y1 ([inr k1, inr k2] ++ z)) @
     amal_mu_K (x0 ++ y1) z k1 k2) @
    ap amal_eta (app_assoc x0 y1 ([inr (k1 * k2)] ++ z))^)
   (fun (y1 w : Words) (z : G) =>
    (ap amal_eta (app_assoc x0 y1 ([inl (f z)] ++ w)) @
     amal_tau (x0 ++ y1) w z) @
    ap amal_eta (app_assoc x0 y1 ([inr (g z)] ++ w))^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inl mon_unit] ++ z)) @
     amal_omega_H (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inr mon_unit] ++ z)) @
     amal_omega_K (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   y)
  (x ++ y0)
    {
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: Words
forall (y : amal_type) (y0 : Words),
(fun x0 : Words =>
 amal_type_rec amal_type (fun y1 : Words => amal_eta (x0 ++ y1))
   (fun (y1 z : Words) (h1 h2 : H) =>
    (ap amal_eta (app_assoc x0 y1 ([inl h1, inl h2] ++ z)) @
     amal_mu_H (x0 ++ y1) z h1 h2) @
    ap amal_eta (app_assoc x0 y1 ([inl (h1 * h2)] ++ z))^)
   (fun (y1 z : Words) (k1 k2 : K) =>
    (ap amal_eta (app_assoc x0 y1 ([inr k1, inr k2] ++ z)) @
     amal_mu_K (x0 ++ y1) z k1 k2) @
    ap amal_eta (app_assoc x0 y1 ([inr (k1 * k2)] ++ z))^)
   (fun (y1 w : Words) (z : G) =>
    (ap amal_eta (app_assoc x0 y1 ([inl (f z)] ++ w)) @
     amal_tau (x0 ++ y1) w z) @
    ap amal_eta (app_assoc x0 y1 ([inr (g z)] ++ w))^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inl mon_unit] ++ z)) @
     amal_omega_H (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inr mon_unit] ++ z)) @
     amal_omega_K (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   y)
  (x ++ [inl 1] ++ y0) =
(fun x0 : Words =>
 amal_type_rec amal_type (fun y1 : Words => amal_eta (x0 ++ y1))
   (fun (y1 z : Words) (h1 h2 : H) =>
    (ap amal_eta (app_assoc x0 y1 ([inl h1, inl h2] ++ z)) @
     amal_mu_H (x0 ++ y1) z h1 h2) @
    ap amal_eta (app_assoc x0 y1 ([inl (h1 * h2)] ++ z))^)
   (fun (y1 z : Words) (k1 k2 : K) =>
    (ap amal_eta (app_assoc x0 y1 ([inr k1, inr k2] ++ z)) @
     amal_mu_K (x0 ++ y1) z k1 k2) @
    ap amal_eta (app_assoc x0 y1 ([inr (k1 * k2)] ++ z))^)
   (fun (y1 w : Words) (z : G) =>
    (ap amal_eta (app_assoc x0 y1 ([inl (f z)] ++ w)) @
     amal_tau (x0 ++ y1) w z) @
    ap amal_eta (app_assoc x0 y1 ([inr (g z)] ++ w))^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inl mon_unit] ++ z)) @
     amal_omega_H (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inr mon_unit] ++ z)) @
     amal_omega_K (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   y)
  (x ++ y0) intros r z; revert r.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z: Words
forall r : amal_type,
(fun x0 : Words =>
 amal_type_rec amal_type (fun y : Words => amal_eta (x0 ++ y))
   (fun (y z0 : Words) (h1 h2 : H) =>
    (ap amal_eta (app_assoc x0 y ([inl h1, inl h2] ++ z0)) @
     amal_mu_H (x0 ++ y) z0 h1 h2) @
    ap amal_eta (app_assoc x0 y ([inl (h1 * h2)] ++ z0))^)
   (fun (y z0 : Words) (k1 k2 : K) =>
    (ap amal_eta (app_assoc x0 y ([inr k1, inr k2] ++ z0)) @
     amal_mu_K (x0 ++ y) z0 k1 k2) @
    ap amal_eta (app_assoc x0 y ([inr (k1 * k2)] ++ z0))^)
   (fun (y w : Words) (z0 : G) =>
    (ap amal_eta (app_assoc x0 y ([inl (f z0)] ++ w)) @
     amal_tau (x0 ++ y) w z0) @
    ap amal_eta (app_assoc x0 y ([inr (g z0)] ++ w))^)
   (fun y z0 : Words =>
    (ap amal_eta (app_assoc x0 y ([inl mon_unit] ++ z0)) @
     amal_omega_H (x0 ++ y) z0) @
    ap amal_eta (app_assoc x0 y z0)^)
   (fun y z0 : Words =>
    (ap amal_eta (app_assoc x0 y ([inr mon_unit] ++ z0)) @
     amal_omega_K (x0 ++ y) z0) @
    ap amal_eta (app_assoc x0 y z0)^)
   r)
  (x ++ [inl 1] ++ z) =
(fun x0 : Words =>
 amal_type_rec amal_type (fun y : Words => amal_eta (x0 ++ y))
   (fun (y z0 : Words) (h1 h2 : H) =>
    (ap amal_eta (app_assoc x0 y ([inl h1, inl h2] ++ z0)) @
     amal_mu_H (x0 ++ y) z0 h1 h2) @
    ap amal_eta (app_assoc x0 y ([inl (h1 * h2)] ++ z0))^)
   (fun (y z0 : Words) (k1 k2 : K) =>
    (ap amal_eta (app_assoc x0 y ([inr k1, inr k2] ++ z0)) @
     amal_mu_K (x0 ++ y) z0 k1 k2) @
    ap amal_eta (app_assoc x0 y ([inr (k1 * k2)] ++ z0))^)
   (fun (y w : Words) (z0 : G) =>
    (ap amal_eta (app_assoc x0 y ([inl (f z0)] ++ w)) @
     amal_tau (x0 ++ y) w z0) @
    ap amal_eta (app_assoc x0 y ([inr (g z0)] ++ w))^)
   (fun y z0 : Words =>
    (ap amal_eta (app_assoc x0 y ([inl mon_unit] ++ z0)) @
     amal_omega_H (x0 ++ y) z0) @
    ap amal_eta (app_assoc x0 y z0)^)
   (fun y z0 : Words =>
    (ap amal_eta (app_assoc x0 y ([inr mon_unit] ++ z0)) @
     amal_omega_K (x0 ++ y) z0) @
    ap amal_eta (app_assoc x0 y z0)^)
   r)
  (x ++ z)
      rapply amal_type_ind_hprop.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z: Words
forall w : Words,
amal_type_rec amal_type
  (fun y : Words => amal_eta ((x ++ [inl 1] ++ z) ++ y))
  (fun (y z0 : Words) (h1 h2 : H) =>
   (ap amal_eta
      (app_assoc (x ++ [inl mon_unit] ++ z) y ([inl h1, inl h2] ++ z0)) @
    amal_mu_H ((x ++ [inl mon_unit] ++ z) ++ y) z0 h1 h2) @
   ap amal_eta
     (app_assoc (x ++ [inl mon_unit] ++ z) y ([inl (h1 * h2)] ++ z0))^)
  (fun (y z0 : Words) (k1 k2 : K) =>
   (ap amal_eta
      (app_assoc (x ++ [inl mon_unit] ++ z) y ([inr k1, inr k2] ++ z0)) @
    amal_mu_K ((x ++ [inl mon_unit] ++ z) ++ y) z0 k1 k2) @
   ap amal_eta
     (app_assoc (x ++ [inl mon_unit] ++ z) y ([inr (k1 * k2)] ++ z0))^)
  (fun (y w0 : Words) (z0 : G) =>
   (ap amal_eta (app_assoc (x ++ [inl mon_unit] ++ z) y ([inl (f z0)] ++ w0)) @
    amal_tau ((x ++ [inl mon_unit] ++ z) ++ y) w0 z0) @
   ap amal_eta (app_assoc (x ++ [inl mon_unit] ++ z) y ([inr (g z0)] ++ w0))^)
  (fun y z0 : Words =>
   (ap amal_eta
      (app_assoc (x ++ [inl mon_unit] ++ z) y ([inl mon_unit] ++ z0)) @
    amal_omega_H ((x ++ [inl mon_unit] ++ z) ++ y) z0) @
   ap amal_eta (app_assoc (x ++ [inl mon_unit] ++ z) y z0)^)
  (fun y z0 : Words =>
   (ap amal_eta
      (app_assoc (x ++ [inl mon_unit] ++ z) y ([inr mon_unit] ++ z0)) @
    amal_omega_K ((x ++ [inl mon_unit] ++ z) ++ y) z0) @
   ap amal_eta (app_assoc (x ++ [inl mon_unit] ++ z) y z0)^)
  (amal_eta w) =
amal_type_rec amal_type (fun y : Words => amal_eta ((x ++ z) ++ y))
  (fun (y z0 : Words) (h1 h2 : H) =>
   (ap amal_eta (app_assoc (x ++ z) y ([inl h1, inl h2] ++ z0)) @
    amal_mu_H ((x ++ z) ++ y) z0 h1 h2) @
   ap amal_eta (app_assoc (x ++ z) y ([inl (h1 * h2)] ++ z0))^)
  (fun (y z0 : Words) (k1 k2 : K) =>
   (ap amal_eta (app_assoc (x ++ z) y ([inr k1, inr k2] ++ z0)) @
    amal_mu_K ((x ++ z) ++ y) z0 k1 k2) @
   ap amal_eta (app_assoc (x ++ z) y ([inr (k1 * k2)] ++ z0))^)
  (fun (y w0 : Words) (z0 : G) =>
   (ap amal_eta (app_assoc (x ++ z) y ([inl (f z0)] ++ w0)) @
    amal_tau ((x ++ z) ++ y) w0 z0) @
   ap amal_eta (app_assoc (x ++ z) y ([inr (g z0)] ++ w0))^)
  (fun y z0 : Words =>
   (ap amal_eta (app_assoc (x ++ z) y ([inl mon_unit] ++ z0)) @
    amal_omega_H ((x ++ z) ++ y) z0) @
   ap amal_eta (app_assoc (x ++ z) y z0)^)
  (fun y z0 : Words =>
   (ap amal_eta (app_assoc (x ++ z) y ([inr mon_unit] ++ z0)) @
    amal_omega_K ((x ++ z) ++ y) z0) @
   ap amal_eta (app_assoc (x ++ z) y z0)^)
  (amal_eta w)
      intros w;
      change (amal_eta ((x ++ [inl mon_unit] ++ z) ++ w) = amal_eta ((x ++ z) ++ w)).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z, w: Words
amal_eta ((x ++ [inl 1] ++ z) ++ w) = amal_eta ((x ++ z) ++ w)
      refine (ap amal_eta _^ @ _ @ ap amal_eta _).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z, w: Words
?Goal0 = (x ++ [inl 1] ++ z) ++ w
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z, w: Words
amal_eta ?Goal0 = amal_eta ?Goal3
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z, w: Words
?Goal3 = (x ++ z) ++ w
      1,3: apply app_assoc.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z, w: Words
amal_eta (x ++ ([inl 1] ++ z) ++ w) = amal_eta (x ++ z ++ w)
      refine (ap amal_eta (ap (app x) _)^ @ _).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z, w: Words
?Goal0 = ([inl 1] ++ z) ++ w
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z, w: Words
amal_eta (x ++ ?Goal0) = amal_eta (x ++ z ++ w)
      1: apply app_assoc.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z, w: Words
amal_eta (x ++ [inl 1] ++ z ++ w) = amal_eta (x ++ z ++ w)
      apply amal_omega_H. }
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: Words
forall (y : amal_type) (y0 : Words),
(fun x0 : Words =>
 amal_type_rec amal_type (fun y1 : Words => amal_eta (x0 ++ y1))
   (fun (y1 z : Words) (h1 h2 : H) =>
    (ap amal_eta (app_assoc x0 y1 ([inl h1, inl h2] ++ z)) @
     amal_mu_H (x0 ++ y1) z h1 h2) @
    ap amal_eta (app_assoc x0 y1 ([inl (h1 * h2)] ++ z))^)
   (fun (y1 z : Words) (k1 k2 : K) =>
    (ap amal_eta (app_assoc x0 y1 ([inr k1, inr k2] ++ z)) @
     amal_mu_K (x0 ++ y1) z k1 k2) @
    ap amal_eta (app_assoc x0 y1 ([inr (k1 * k2)] ++ z))^)
   (fun (y1 w : Words) (z : G) =>
    (ap amal_eta (app_assoc x0 y1 ([inl (f z)] ++ w)) @
     amal_tau (x0 ++ y1) w z) @
    ap amal_eta (app_assoc x0 y1 ([inr (g z)] ++ w))^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inl mon_unit] ++ z)) @
     amal_omega_H (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inr mon_unit] ++ z)) @
     amal_omega_K (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   y)
  (x ++ [inr 1] ++ y0) =
(fun x0 : Words =>
 amal_type_rec amal_type (fun y1 : Words => amal_eta (x0 ++ y1))
   (fun (y1 z : Words) (h1 h2 : H) =>
    (ap amal_eta (app_assoc x0 y1 ([inl h1, inl h2] ++ z)) @
     amal_mu_H (x0 ++ y1) z h1 h2) @
    ap amal_eta (app_assoc x0 y1 ([inl (h1 * h2)] ++ z))^)
   (fun (y1 z : Words) (k1 k2 : K) =>
    (ap amal_eta (app_assoc x0 y1 ([inr k1, inr k2] ++ z)) @
     amal_mu_K (x0 ++ y1) z k1 k2) @
    ap amal_eta (app_assoc x0 y1 ([inr (k1 * k2)] ++ z))^)
   (fun (y1 w : Words) (z : G) =>
    (ap amal_eta (app_assoc x0 y1 ([inl (f z)] ++ w)) @
     amal_tau (x0 ++ y1) w z) @
    ap amal_eta (app_assoc x0 y1 ([inr (g z)] ++ w))^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inl mon_unit] ++ z)) @
     amal_omega_H (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inr mon_unit] ++ z)) @
     amal_omega_K (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   y)
  (x ++ y0)
    {
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: Words
forall (y : amal_type) (y0 : Words),
(fun x0 : Words =>
 amal_type_rec amal_type (fun y1 : Words => amal_eta (x0 ++ y1))
   (fun (y1 z : Words) (h1 h2 : H) =>
    (ap amal_eta (app_assoc x0 y1 ([inl h1, inl h2] ++ z)) @
     amal_mu_H (x0 ++ y1) z h1 h2) @
    ap amal_eta (app_assoc x0 y1 ([inl (h1 * h2)] ++ z))^)
   (fun (y1 z : Words) (k1 k2 : K) =>
    (ap amal_eta (app_assoc x0 y1 ([inr k1, inr k2] ++ z)) @
     amal_mu_K (x0 ++ y1) z k1 k2) @
    ap amal_eta (app_assoc x0 y1 ([inr (k1 * k2)] ++ z))^)
   (fun (y1 w : Words) (z : G) =>
    (ap amal_eta (app_assoc x0 y1 ([inl (f z)] ++ w)) @
     amal_tau (x0 ++ y1) w z) @
    ap amal_eta (app_assoc x0 y1 ([inr (g z)] ++ w))^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inl mon_unit] ++ z)) @
     amal_omega_H (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inr mon_unit] ++ z)) @
     amal_omega_K (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   y)
  (x ++ [inr 1] ++ y0) =
(fun x0 : Words =>
 amal_type_rec amal_type (fun y1 : Words => amal_eta (x0 ++ y1))
   (fun (y1 z : Words) (h1 h2 : H) =>
    (ap amal_eta (app_assoc x0 y1 ([inl h1, inl h2] ++ z)) @
     amal_mu_H (x0 ++ y1) z h1 h2) @
    ap amal_eta (app_assoc x0 y1 ([inl (h1 * h2)] ++ z))^)
   (fun (y1 z : Words) (k1 k2 : K) =>
    (ap amal_eta (app_assoc x0 y1 ([inr k1, inr k2] ++ z)) @
     amal_mu_K (x0 ++ y1) z k1 k2) @
    ap amal_eta (app_assoc x0 y1 ([inr (k1 * k2)] ++ z))^)
   (fun (y1 w : Words) (z : G) =>
    (ap amal_eta (app_assoc x0 y1 ([inl (f z)] ++ w)) @
     amal_tau (x0 ++ y1) w z) @
    ap amal_eta (app_assoc x0 y1 ([inr (g z)] ++ w))^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inl mon_unit] ++ z)) @
     amal_omega_H (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   (fun y1 z : Words =>
    (ap amal_eta (app_assoc x0 y1 ([inr mon_unit] ++ z)) @
     amal_omega_K (x0 ++ y1) z) @
    ap amal_eta (app_assoc x0 y1 z)^)
   y)
  (x ++ y0) intros r z; revert r.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z: Words
forall r : amal_type,
(fun x0 : Words =>
 amal_type_rec amal_type (fun y : Words => amal_eta (x0 ++ y))
   (fun (y z0 : Words) (h1 h2 : H) =>
    (ap amal_eta (app_assoc x0 y ([inl h1, inl h2] ++ z0)) @
     amal_mu_H (x0 ++ y) z0 h1 h2) @
    ap amal_eta (app_assoc x0 y ([inl (h1 * h2)] ++ z0))^)
   (fun (y z0 : Words) (k1 k2 : K) =>
    (ap amal_eta (app_assoc x0 y ([inr k1, inr k2] ++ z0)) @
     amal_mu_K (x0 ++ y) z0 k1 k2) @
    ap amal_eta (app_assoc x0 y ([inr (k1 * k2)] ++ z0))^)
   (fun (y w : Words) (z0 : G) =>
    (ap amal_eta (app_assoc x0 y ([inl (f z0)] ++ w)) @
     amal_tau (x0 ++ y) w z0) @
    ap amal_eta (app_assoc x0 y ([inr (g z0)] ++ w))^)
   (fun y z0 : Words =>
    (ap amal_eta (app_assoc x0 y ([inl mon_unit] ++ z0)) @
     amal_omega_H (x0 ++ y) z0) @
    ap amal_eta (app_assoc x0 y z0)^)
   (fun y z0 : Words =>
    (ap amal_eta (app_assoc x0 y ([inr mon_unit] ++ z0)) @
     amal_omega_K (x0 ++ y) z0) @
    ap amal_eta (app_assoc x0 y z0)^)
   r)
  (x ++ [inr 1] ++ z) =
(fun x0 : Words =>
 amal_type_rec amal_type (fun y : Words => amal_eta (x0 ++ y))
   (fun (y z0 : Words) (h1 h2 : H) =>
    (ap amal_eta (app_assoc x0 y ([inl h1, inl h2] ++ z0)) @
     amal_mu_H (x0 ++ y) z0 h1 h2) @
    ap amal_eta (app_assoc x0 y ([inl (h1 * h2)] ++ z0))^)
   (fun (y z0 : Words) (k1 k2 : K) =>
    (ap amal_eta (app_assoc x0 y ([inr k1, inr k2] ++ z0)) @
     amal_mu_K (x0 ++ y) z0 k1 k2) @
    ap amal_eta (app_assoc x0 y ([inr (k1 * k2)] ++ z0))^)
   (fun (y w : Words) (z0 : G) =>
    (ap amal_eta (app_assoc x0 y ([inl (f z0)] ++ w)) @
     amal_tau (x0 ++ y) w z0) @
    ap amal_eta (app_assoc x0 y ([inr (g z0)] ++ w))^)
   (fun y z0 : Words =>
    (ap amal_eta (app_assoc x0 y ([inl mon_unit] ++ z0)) @
     amal_omega_H (x0 ++ y) z0) @
    ap amal_eta (app_assoc x0 y z0)^)
   (fun y z0 : Words =>
    (ap amal_eta (app_assoc x0 y ([inr mon_unit] ++ z0)) @
     amal_omega_K (x0 ++ y) z0) @
    ap amal_eta (app_assoc x0 y z0)^)
   r)
  (x ++ z)
      rapply amal_type_ind_hprop.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z: Words
forall w : Words,
amal_type_rec amal_type
  (fun y : Words => amal_eta ((x ++ [inr 1] ++ z) ++ y))
  (fun (y z0 : Words) (h1 h2 : H) =>
   (ap amal_eta
      (app_assoc (x ++ [inr mon_unit] ++ z) y ([inl h1, inl h2] ++ z0)) @
    amal_mu_H ((x ++ [inr mon_unit] ++ z) ++ y) z0 h1 h2) @
   ap amal_eta
     (app_assoc (x ++ [inr mon_unit] ++ z) y ([inl (h1 * h2)] ++ z0))^)
  (fun (y z0 : Words) (k1 k2 : K) =>
   (ap amal_eta
      (app_assoc (x ++ [inr mon_unit] ++ z) y ([inr k1, inr k2] ++ z0)) @
    amal_mu_K ((x ++ [inr mon_unit] ++ z) ++ y) z0 k1 k2) @
   ap amal_eta
     (app_assoc (x ++ [inr mon_unit] ++ z) y ([inr (k1 * k2)] ++ z0))^)
  (fun (y w0 : Words) (z0 : G) =>
   (ap amal_eta (app_assoc (x ++ [inr mon_unit] ++ z) y ([inl (f z0)] ++ w0)) @
    amal_tau ((x ++ [inr mon_unit] ++ z) ++ y) w0 z0) @
   ap amal_eta (app_assoc (x ++ [inr mon_unit] ++ z) y ([inr (g z0)] ++ w0))^)
  (fun y z0 : Words =>
   (ap amal_eta
      (app_assoc (x ++ [inr mon_unit] ++ z) y ([inl mon_unit] ++ z0)) @
    amal_omega_H ((x ++ [inr mon_unit] ++ z) ++ y) z0) @
   ap amal_eta (app_assoc (x ++ [inr mon_unit] ++ z) y z0)^)
  (fun y z0 : Words =>
   (ap amal_eta
      (app_assoc (x ++ [inr mon_unit] ++ z) y ([inr mon_unit] ++ z0)) @
    amal_omega_K ((x ++ [inr mon_unit] ++ z) ++ y) z0) @
   ap amal_eta (app_assoc (x ++ [inr mon_unit] ++ z) y z0)^)
  (amal_eta w) =
amal_type_rec amal_type (fun y : Words => amal_eta ((x ++ z) ++ y))
  (fun (y z0 : Words) (h1 h2 : H) =>
   (ap amal_eta (app_assoc (x ++ z) y ([inl h1, inl h2] ++ z0)) @
    amal_mu_H ((x ++ z) ++ y) z0 h1 h2) @
   ap amal_eta (app_assoc (x ++ z) y ([inl (h1 * h2)] ++ z0))^)
  (fun (y z0 : Words) (k1 k2 : K) =>
   (ap amal_eta (app_assoc (x ++ z) y ([inr k1, inr k2] ++ z0)) @
    amal_mu_K ((x ++ z) ++ y) z0 k1 k2) @
   ap amal_eta (app_assoc (x ++ z) y ([inr (k1 * k2)] ++ z0))^)
  (fun (y w0 : Words) (z0 : G) =>
   (ap amal_eta (app_assoc (x ++ z) y ([inl (f z0)] ++ w0)) @
    amal_tau ((x ++ z) ++ y) w0 z0) @
   ap amal_eta (app_assoc (x ++ z) y ([inr (g z0)] ++ w0))^)
  (fun y z0 : Words =>
   (ap amal_eta (app_assoc (x ++ z) y ([inl mon_unit] ++ z0)) @
    amal_omega_H ((x ++ z) ++ y) z0) @
   ap amal_eta (app_assoc (x ++ z) y z0)^)
  (fun y z0 : Words =>
   (ap amal_eta (app_assoc (x ++ z) y ([inr mon_unit] ++ z0)) @
    amal_omega_K ((x ++ z) ++ y) z0) @
   ap amal_eta (app_assoc (x ++ z) y z0)^)
  (amal_eta w)
      intros w;
      change (amal_eta ((x ++ [inr mon_unit] ++ z) ++ w) = amal_eta ((x ++ z) ++ w)).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z, w: Words
amal_eta ((x ++ [inr 1] ++ z) ++ w) = amal_eta ((x ++ z) ++ w)
      refine (ap amal_eta _^ @ _ @ ap amal_eta _).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z, w: Words
?Goal = (x ++ [inr 1] ++ z) ++ w
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z, w: Words
amal_eta ?Goal = amal_eta ?Goal2
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z, w: Words
?Goal2 = (x ++ z) ++ w
      1,3: apply app_assoc.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z, w: Words
amal_eta (x ++ ([inr 1] ++ z) ++ w) = amal_eta (x ++ z ++ w)
      refine (ap amal_eta (ap (app x) _)^ @ _).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z, w: Words
?Goal = ([inr 1] ++ z) ++ w
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z, w: Words
amal_eta (x ++ ?Goal) = amal_eta (x ++ z ++ w)
      1: apply app_assoc.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z, w: Words
amal_eta (x ++ [inr 1] ++ z ++ w) = amal_eta (x ++ z ++ w)
      apply amal_omega_K. }
  Defined.

  (** The identity element is the empty list *)
  Local Instance monunit_amal_type : MonUnit amal_type.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
MonUnit amal_type
  Proof.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
MonUnit amal_type
    exact (amal_eta nil).
  Defined.

  Local Instance inverse_amal_type : Inverse amal_type.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
Inverse amal_type
  Proof.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
Inverse amal_type
    srapply amal_type_rec.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
Words -> amal_type
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
forall (x y : Words) (h1 h2 : H),
?e (x ++ [inl h1, inl h2] ++ y) = ?e (x ++ [inl (h1 * h2)] ++ y)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
forall (x y : Words) (k1 k2 : K),
?e (x ++ [inr k1, inr k2] ++ y) = ?e (x ++ [inr (k1 * k2)] ++ y)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
forall (x y : Words) (z : G),
?e (x ++ [inl (f z)] ++ y) = ?e (x ++ [inr (g z)] ++ y)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
forall x y : Words, ?e (x ++ [inl 1] ++ y) = ?e (x ++ y)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
forall x y : Words, ?e (x ++ [inr 1] ++ y) = ?e (x ++ y)
    {
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
Words -> amal_type intros w.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
w: Words
amal_type
      exact (amal_eta (word_inverse w)). }
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
forall (x y : Words) (h1 h2 : H),
(fun w : Words => amal_eta (word_inverse w)) (x ++ [inl h1, inl h2] ++ y) =
(fun w : Words => amal_eta (word_inverse w)) (x ++ [inl (h1 * h2)] ++ y)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
forall (x y : Words) (k1 k2 : K),
(fun w : Words => amal_eta (word_inverse w)) (x ++ [inr k1, inr k2] ++ y) =
(fun w : Words => amal_eta (word_inverse w)) (x ++ [inr (k1 * k2)] ++ y)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
forall (x y : Words) (z : G),
(fun w : Words => amal_eta (word_inverse w)) (x ++ [inl (f z)] ++ y) =
(fun w : Words => amal_eta (word_inverse w)) (x ++ [inr (g z)] ++ y)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
forall x y : Words,
(fun w : Words => amal_eta (word_inverse w)) (x ++ [inl 1] ++ y) =
(fun w : Words => amal_eta (word_inverse w)) (x ++ y)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
forall x y : Words,
(fun w : Words => amal_eta (word_inverse w)) (x ++ [inr 1] ++ y) =
(fun w : Words => amal_eta (word_inverse w)) (x ++ y)
    {
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
forall (x y : Words) (h1 h2 : H),
(fun w : Words => amal_eta (word_inverse w)) (x ++ [inl h1, inl h2] ++ y) =
(fun w : Words => amal_eta (word_inverse w)) (x ++ [inl (h1 * h2)] ++ y) hnf; intros x y h1 h2.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
h1, h2: H
amal_eta (word_inverse (x ++ [inl h1, inl h2] ++ y)) =
amal_eta (word_inverse (x ++ [inl (h1 * h2)] ++ y))
      refine (ap amal_eta _ @ _ @ ap amal_eta _^).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
h1, h2: H
word_inverse (x ++ [inl h1, inl h2] ++ y) = ?Goal
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
h1, h2: H
amal_eta ?Goal = amal_eta ?Goal2
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
h1, h2: H
word_inverse (x ++ [inl (h1 * h2)] ++ y) = ?Goal2
      1,3: refine (word_inverse_ww _ _ @ ap (fun s => s ++ _) _).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
h1, h2: H
word_inverse ([inl h1, inl h2] ++ y) = ?Goal0
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
h1, h2: H
word_inverse ([inl (h1 * h2)] ++ y) = ?Goal2
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
h1, h2: H
amal_eta (?Goal0 ++ word_inverse x) = amal_eta (?Goal2 ++ word_inverse x)
      1: apply word_inverse_ww.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
h1, h2: H
word_inverse ([inl (h1 * h2)] ++ y) = ?Goal0
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
h1, h2: H
amal_eta
  ((word_inverse y ++ word_inverse [inl h1, inl h2]) ++ word_inverse x) =
amal_eta (?Goal0 ++ word_inverse x)
      {
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
h1, h2: H
word_inverse ([inl (h1 * h2)] ++ y) = ?Goal0 refine (word_inverse_ww _ _ @ _).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
h1, h2: H
word_inverse y ++ word_inverse [inl (h1 * h2)] = ?Goal0
        apply ap; simpl.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
h1, h2: H
[inl (h1 * h2)^] = ?y
        rapply (ap (fun s => [s])).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
h1, h2: H
inl (h1 * h2)^ = ?Goal0
        apply ap.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
h1, h2: H
(h1 * h2)^ = ?y
        apply inverse_sg_op. }
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
h1, h2: H
amal_eta
  ((word_inverse y ++ word_inverse [inl h1, inl h2]) ++ word_inverse x) =
amal_eta ((word_inverse y ++ [inl (h2^ * h1^)]) ++ word_inverse x)
      simpl.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
h1, h2: H
amal_eta ((word_inverse y ++ [inl h2^, inl h1^]) ++ word_inverse x) =
amal_eta ((word_inverse y ++ [inl (h2^ * h1^)]) ++ word_inverse x)
      refine (ap amal_eta _^ @ _ @ ap amal_eta _).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
h1, h2: H
?Goal = (word_inverse y ++ [inl h2^, inl h1^]) ++ word_inverse x
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
h1, h2: H
amal_eta ?Goal = amal_eta ?Goal2
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
h1, h2: H
?Goal2 = (word_inverse y ++ [inl (h2^ * h1^)]) ++ word_inverse x
      1,3: apply app_assoc.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
h1, h2: H
amal_eta (word_inverse y ++ [inl h2^, inl h1^] ++ word_inverse x) =
amal_eta (word_inverse y ++ [inl (h2^ * h1^)] ++ word_inverse x)
      apply amal_mu_H. }
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
forall (x y : Words) (k1 k2 : K),
(fun w : Words => amal_eta (word_inverse w)) (x ++ [inr k1, inr k2] ++ y) =
(fun w : Words => amal_eta (word_inverse w)) (x ++ [inr (k1 * k2)] ++ y)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
forall (x y : Words) (z : G),
(fun w : Words => amal_eta (word_inverse w)) (x ++ [inl (f z)] ++ y) =
(fun w : Words => amal_eta (word_inverse w)) (x ++ [inr (g z)] ++ y)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
forall x y : Words,
(fun w : Words => amal_eta (word_inverse w)) (x ++ [inl 1] ++ y) =
(fun w : Words => amal_eta (word_inverse w)) (x ++ y)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
forall x y : Words,
(fun w : Words => amal_eta (word_inverse w)) (x ++ [inr 1] ++ y) =
(fun w : Words => amal_eta (word_inverse w)) (x ++ y)
    {
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
forall (x y : Words) (k1 k2 : K),
(fun w : Words => amal_eta (word_inverse w)) (x ++ [inr k1, inr k2] ++ y) =
(fun w : Words => amal_eta (word_inverse w)) (x ++ [inr (k1 * k2)] ++ y) hnf; intros x y k1 k2.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
k1, k2: K
amal_eta (word_inverse (x ++ [inr k1, inr k2] ++ y)) =
amal_eta (word_inverse (x ++ [inr (k1 * k2)] ++ y))
      refine (ap amal_eta _ @ _ @ ap amal_eta _^).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
k1, k2: K
word_inverse (x ++ [inr k1, inr k2] ++ y) = ?Goal
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
k1, k2: K
amal_eta ?Goal = amal_eta ?Goal2
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
k1, k2: K
word_inverse (x ++ [inr (k1 * k2)] ++ y) = ?Goal2
      1,3: refine (word_inverse_ww _ _ @ ap (fun s => s ++ _) _).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
k1, k2: K
word_inverse ([inr k1, inr k2] ++ y) = ?Goal0
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
k1, k2: K
word_inverse ([inr (k1 * k2)] ++ y) = ?Goal2
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
k1, k2: K
amal_eta (?Goal0 ++ word_inverse x) = amal_eta (?Goal2 ++ word_inverse x)
      1: apply word_inverse_ww.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
k1, k2: K
word_inverse ([inr (k1 * k2)] ++ y) = ?Goal0
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
k1, k2: K
amal_eta
  ((word_inverse y ++ word_inverse [inr k1, inr k2]) ++ word_inverse x) =
amal_eta (?Goal0 ++ word_inverse x)
      {
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
k1, k2: K
word_inverse ([inr (k1 * k2)] ++ y) = ?Goal0 refine (word_inverse_ww _ _ @ _).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
k1, k2: K
word_inverse y ++ word_inverse [inr (k1 * k2)] = ?Goal0
        apply ap; simpl.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
k1, k2: K
[inr (k1 * k2)^] = ?y
        rapply (ap (fun s => [s])).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
k1, k2: K
inr (k1 * k2)^ = ?Goal0
        apply ap.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
k1, k2: K
(k1 * k2)^ = ?y
        apply inverse_sg_op. }
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
k1, k2: K
amal_eta
  ((word_inverse y ++ word_inverse [inr k1, inr k2]) ++ word_inverse x) =
amal_eta ((word_inverse y ++ [inr (k2^ * k1^)]) ++ word_inverse x)
      simpl.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
k1, k2: K
amal_eta ((word_inverse y ++ [inr k2^, inr k1^]) ++ word_inverse x) =
amal_eta ((word_inverse y ++ [inr (k2^ * k1^)]) ++ word_inverse x)
      refine (ap amal_eta _^ @ _ @ ap amal_eta _).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
k1, k2: K
?Goal = (word_inverse y ++ [inr k2^, inr k1^]) ++ word_inverse x
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
k1, k2: K
amal_eta ?Goal = amal_eta ?Goal2
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
k1, k2: K
?Goal2 = (word_inverse y ++ [inr (k2^ * k1^)]) ++ word_inverse x
      1,3: apply app_assoc.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
k1, k2: K
amal_eta (word_inverse y ++ [inr k2^, inr k1^] ++ word_inverse x) =
amal_eta (word_inverse y ++ [inr (k2^ * k1^)] ++ word_inverse x)
      apply amal_mu_K. }
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
forall (x y : Words) (z : G),
(fun w : Words => amal_eta (word_inverse w)) (x ++ [inl (f z)] ++ y) =
(fun w : Words => amal_eta (word_inverse w)) (x ++ [inr (g z)] ++ y)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
forall x y : Words,
(fun w : Words => amal_eta (word_inverse w)) (x ++ [inl 1] ++ y) =
(fun w : Words => amal_eta (word_inverse w)) (x ++ y)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
forall x y : Words,
(fun w : Words => amal_eta (word_inverse w)) (x ++ [inr 1] ++ y) =
(fun w : Words => amal_eta (word_inverse w)) (x ++ y)
    {
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
forall (x y : Words) (z : G),
(fun w : Words => amal_eta (word_inverse w)) (x ++ [inl (f z)] ++ y) =
(fun w : Words => amal_eta (word_inverse w)) (x ++ [inr (g z)] ++ y) hnf; intros x y z.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
z: G
amal_eta (word_inverse (x ++ [inl (f z)] ++ y)) =
amal_eta (word_inverse (x ++ [inr (g z)] ++ y))
      refine (ap amal_eta _ @ _ @ ap amal_eta _^).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
z: G
word_inverse (x ++ [inl (f z)] ++ y) = ?Goal
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
z: G
amal_eta ?Goal = amal_eta ?Goal2
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
z: G
word_inverse (x ++ [inr (g z)] ++ y) = ?Goal2
      1,3: refine (word_inverse_ww _ _ @ ap (fun s => s ++ _) _).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
z: G
word_inverse ([inl (f z)] ++ y) = ?Goal0
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
z: G
word_inverse ([inr (g z)] ++ y) = ?Goal2
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
z: G
amal_eta (?Goal0 ++ word_inverse x) = amal_eta (?Goal2 ++ word_inverse x)
      1,2: cbn; refine (ap _ _).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
z: G
[inl (f z)^] = ?Goal0
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
z: G
[inr (g z)^] = ?Goal2
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
z: G
amal_eta ((word_inverse y ++ ?Goal0) ++ word_inverse x) =
amal_eta ((word_inverse y ++ ?Goal2) ++ word_inverse x)
      1,2: rapply (ap (fun s => [s])).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
z: G
inl (f z)^ = ?Goal0
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
z: G
inr (g z)^ = ?Goal2
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
z: G
amal_eta ((word_inverse y ++ [?Goal0]) ++ word_inverse x) =
amal_eta ((word_inverse y ++ [?Goal2]) ++ word_inverse x)
      1,2: apply ap.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
z: G
(f z)^ = ?y
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
z: G
(g z)^ = ?y0
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
z: G
amal_eta ((word_inverse y ++ [inl ?y]) ++ word_inverse x) =
amal_eta ((word_inverse y ++ [inr ?y0]) ++ word_inverse x)
      1,2: symmetry; apply grp_homo_inv.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
z: G
amal_eta ((word_inverse y ++ [inl (f z^)]) ++ word_inverse x) =
amal_eta ((word_inverse y ++ [inr (g z^)]) ++ word_inverse x)
      refine (ap amal_eta _^ @ _ @ ap amal_eta _).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
z: G
?Goal = (word_inverse y ++ [inl (f z^)]) ++ word_inverse x
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
z: G
amal_eta ?Goal = amal_eta ?Goal2
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
z: G
?Goal2 = (word_inverse y ++ [inr (g z^)]) ++ word_inverse x
      1,3: apply app_assoc.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: Words
z: G
amal_eta (word_inverse y ++ [inl (f z^)] ++ word_inverse x) =
amal_eta (word_inverse y ++ [inr (g z^)] ++ word_inverse x)
      apply amal_tau. }
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
forall x y : Words,
(fun w : Words => amal_eta (word_inverse w)) (x ++ [inl 1] ++ y) =
(fun w : Words => amal_eta (word_inverse w)) (x ++ y)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
forall x y : Words,
(fun w : Words => amal_eta (word_inverse w)) (x ++ [inr 1] ++ y) =
(fun w : Words => amal_eta (word_inverse w)) (x ++ y)
    {
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
forall x y : Words,
(fun w : Words => amal_eta (word_inverse w)) (x ++ [inl 1] ++ y) =
(fun w : Words => amal_eta (word_inverse w)) (x ++ y) hnf; intros x z.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z: Words
amal_eta (word_inverse (x ++ [inl 1] ++ z)) =
amal_eta (word_inverse (x ++ z))
      refine (ap amal_eta _ @ _ @ ap amal_eta _^).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z: Words
word_inverse (x ++ [inl 1] ++ z) = ?Goal
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z: Words
amal_eta ?Goal = amal_eta ?Goal2
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z: Words
word_inverse (x ++ z) = ?Goal2
      1,3: apply word_inverse_ww.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z: Words
amal_eta (word_inverse ([inl 1] ++ z) ++ word_inverse x) =
amal_eta (word_inverse z ++ word_inverse x)
      refine (ap amal_eta _ @ _).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z: Words
word_inverse ([inl 1] ++ z) ++ word_inverse x = ?Goal
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z: Words
amal_eta ?Goal = amal_eta (word_inverse z ++ word_inverse x)
      {
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z: Words
word_inverse ([inl 1] ++ z) ++ word_inverse x = ?Goal refine (ap (fun s => s ++ _) _).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z: Words
word_inverse ([inl 1] ++ z) = ?Goal0
        apply word_inverse_ww. }
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z: Words
amal_eta ((word_inverse z ++ word_inverse [inl 1]) ++ word_inverse x) =
amal_eta (word_inverse z ++ word_inverse x)
      refine (ap amal_eta _^ @ _).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z: Words
?Goal = (word_inverse z ++ word_inverse [inl 1]) ++ word_inverse x
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z: Words
amal_eta ?Goal = amal_eta (word_inverse z ++ word_inverse x)
      1: apply app_assoc.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z: Words
amal_eta (word_inverse z ++ word_inverse [inl 1] ++ word_inverse x) =
amal_eta (word_inverse z ++ word_inverse x)
      simpl.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z: Words
amal_eta (word_inverse z ++ inl 1^ :: word_inverse x) =
amal_eta (word_inverse z ++ word_inverse x)
      rewrite inverse_mon_unit.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z: Words
amal_eta (word_inverse z ++ inl 1 :: word_inverse x) =
amal_eta (word_inverse z ++ word_inverse x)
      apply amal_omega_H. }
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
forall x y : Words,
(fun w : Words => amal_eta (word_inverse w)) (x ++ [inr 1] ++ y) =
(fun w : Words => amal_eta (word_inverse w)) (x ++ y)
    {
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
forall x y : Words,
(fun w : Words => amal_eta (word_inverse w)) (x ++ [inr 1] ++ y) =
(fun w : Words => amal_eta (word_inverse w)) (x ++ y) hnf; intros x z.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z: Words
amal_eta (word_inverse (x ++ [inr 1] ++ z)) =
amal_eta (word_inverse (x ++ z))
      refine (ap amal_eta _ @ _ @ ap amal_eta _^).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z: Words
word_inverse (x ++ [inr 1] ++ z) = ?Goal
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z: Words
amal_eta ?Goal = amal_eta ?Goal2
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z: Words
word_inverse (x ++ z) = ?Goal2
      1,3: apply word_inverse_ww.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z: Words
amal_eta (word_inverse ([inr 1] ++ z) ++ word_inverse x) =
amal_eta (word_inverse z ++ word_inverse x)
      refine (ap amal_eta _ @ _).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z: Words
word_inverse ([inr 1] ++ z) ++ word_inverse x = ?Goal
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z: Words
amal_eta ?Goal = amal_eta (word_inverse z ++ word_inverse x)
      {
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z: Words
word_inverse ([inr 1] ++ z) ++ word_inverse x = ?Goal refine (ap (fun s => s ++ _) _).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z: Words
word_inverse ([inr 1] ++ z) = ?Goal0
        apply word_inverse_ww. }
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z: Words
amal_eta ((word_inverse z ++ word_inverse [inr 1]) ++ word_inverse x) =
amal_eta (word_inverse z ++ word_inverse x)
      refine (ap amal_eta _^ @ _).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z: Words
?Goal = (word_inverse z ++ word_inverse [inr 1]) ++ word_inverse x
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z: Words
amal_eta ?Goal = amal_eta (word_inverse z ++ word_inverse x)
      1: apply app_assoc.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z: Words
amal_eta (word_inverse z ++ word_inverse [inr 1] ++ word_inverse x) =
amal_eta (word_inverse z ++ word_inverse x)
      simpl.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z: Words
amal_eta (word_inverse z ++ inr 1^ :: word_inverse x) =
amal_eta (word_inverse z ++ word_inverse x)
      rewrite inverse_mon_unit.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, z: Words
amal_eta (word_inverse z ++ inr 1 :: word_inverse x) =
amal_eta (word_inverse z ++ word_inverse x)
      apply amal_omega_K. }
  Defined.

  Local Instance associative_sgop_m : Associative sg_op.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
Associative sg_op
  Proof.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
Associative sg_op
    intros x y.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: amal_type
forall z : amal_type, x * (y * z) = x * y * z
    rapply amal_type_ind_hprop; intro z; revert y.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: amal_type
z: Words
forall y : amal_type, x * (y * amal_eta z) = x * y * amal_eta z
    rapply amal_type_ind_hprop; intro y; revert x.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
z, y: Words
forall x : amal_type,
x * (amal_eta y * amal_eta z) = x * amal_eta y * amal_eta z
    rapply amal_type_ind_hprop; intro x.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
z, y, x: Words
amal_eta x * (amal_eta y * amal_eta z) = amal_eta x * amal_eta y * amal_eta z
    napply (ap amal_eta).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
z, y, x: Words
x ++ y ++ z = (x ++ y) ++ z
    rapply app_assoc.
  Defined.

  Local Instance leftidentity_sgop_amal_type : LeftIdentity sg_op mon_unit.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
LeftIdentity sg_op 1
  Proof.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
LeftIdentity sg_op 1
    rapply amal_type_ind_hprop; intro x.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: Words
1 * amal_eta x = amal_eta x
    reflexivity.
  Defined.

  Local Instance rightidentity_sgop_amal_type : RightIdentity sg_op mon_unit.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
RightIdentity sg_op 1
  Proof.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
RightIdentity sg_op 1
    rapply amal_type_ind_hprop; intro x.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: Words
amal_eta x * 1 = amal_eta x
    napply (ap amal_eta).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: Words
x ++ nil = x
    napply app_nil.
  Defined.

  Lemma amal_eta_word_concat_Vw (x : Words) : amal_eta (word_inverse x ++ x) = mon_unit.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: Words
amal_eta (word_inverse x ++ x) = 1
  Proof.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: Words
amal_eta (word_inverse x ++ x) = 1
    induction x as [|x xs].
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
amal_eta (word_inverse nil ++ nil) = 1
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: H + K
xs: list (H + K)
IHxs: amal_eta (word_inverse xs ++ xs) = 1
amal_eta (word_inverse (x :: xs) ++ x :: xs) = 1
    1: reflexivity.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: H + K
xs: list (H + K)
IHxs: amal_eta (word_inverse xs ++ xs) = 1
amal_eta (word_inverse (x :: xs) ++ x :: xs) = 1
    destruct x as [h|k].
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
h: H
xs: list (H + K)
IHxs: amal_eta (word_inverse xs ++ xs) = 1
amal_eta (word_inverse (inl h :: xs) ++ inl h :: xs) = 1
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
k: K
xs: list (H + K)
IHxs: amal_eta (word_inverse xs ++ xs) = 1
amal_eta (word_inverse (inr k :: xs) ++ inr k :: xs) = 1
    +
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
h: H
xs: list (H + K)
IHxs: amal_eta (word_inverse xs ++ xs) = 1
amal_eta (word_inverse (inl h :: xs) ++ inl h :: xs) = 1 change (amal_eta (word_inverse ([inl h] ++ xs) ++ [inl h] ++ xs) = mon_unit).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
h: H
xs: list (H + K)
IHxs: amal_eta (word_inverse xs ++ xs) = 1
amal_eta (word_inverse ([inl h] ++ xs) ++ [inl h] ++ xs) = 1
      rewrite word_inverse_ww.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
h: H
xs: list (H + K)
IHxs: amal_eta (word_inverse xs ++ xs) = 1
amal_eta ((word_inverse xs ++ word_inverse [inl h]) ++ [inl h] ++ xs) = 1
      rewrite <- app_assoc.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
h: H
xs: list (H + K)
IHxs: amal_eta (word_inverse xs ++ xs) = 1
amal_eta (word_inverse xs ++ word_inverse [inl h] ++ [inl h] ++ xs) = 1
      refine (amal_mu_H _ _ _ _ @ _).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
h: H
xs: list (H + K)
IHxs: amal_eta (word_inverse xs ++ xs) = 1
amal_eta (word_inverse xs ++ [inl (h^ * h)] ++ xs) = 1
      rewrite left_inverse.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
h: H
xs: list (H + K)
IHxs: amal_eta (word_inverse xs ++ xs) = 1
amal_eta (word_inverse xs ++ [inl 1] ++ xs) = 1
      rewrite amal_omega_H.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
h: H
xs: list (H + K)
IHxs: amal_eta (word_inverse xs ++ xs) = 1
amal_eta (word_inverse xs ++ xs) = 1
      exact IHxs.
    +
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
k: K
xs: list (H + K)
IHxs: amal_eta (word_inverse xs ++ xs) = 1
amal_eta (word_inverse (inr k :: xs) ++ inr k :: xs) = 1 change (amal_eta (word_inverse ([inr k] ++ xs) ++ [inr k] ++ xs) = mon_unit).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
k: K
xs: list (H + K)
IHxs: amal_eta (word_inverse xs ++ xs) = 1
amal_eta (word_inverse ([inr k] ++ xs) ++ [inr k] ++ xs) = 1
      rewrite word_inverse_ww.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
k: K
xs: list (H + K)
IHxs: amal_eta (word_inverse xs ++ xs) = 1
amal_eta ((word_inverse xs ++ word_inverse [inr k]) ++ [inr k] ++ xs) = 1
      rewrite <- app_assoc.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
k: K
xs: list (H + K)
IHxs: amal_eta (word_inverse xs ++ xs) = 1
amal_eta (word_inverse xs ++ word_inverse [inr k] ++ [inr k] ++ xs) = 1
      refine (amal_mu_K _ _ _ _ @ _).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
k: K
xs: list (H + K)
IHxs: amal_eta (word_inverse xs ++ xs) = 1
amal_eta (word_inverse xs ++ [inr (k^ * k)] ++ xs) = 1
      rewrite left_inverse.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
k: K
xs: list (H + K)
IHxs: amal_eta (word_inverse xs ++ xs) = 1
amal_eta (word_inverse xs ++ [inr 1] ++ xs) = 1
      rewrite amal_omega_K.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
k: K
xs: list (H + K)
IHxs: amal_eta (word_inverse xs ++ xs) = 1
amal_eta (word_inverse xs ++ xs) = 1
      exact IHxs.
  Defined.

  Lemma amal_eta_word_concat_wV (x : Words) : amal_eta (x ++ word_inverse x) = mon_unit.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: Words
amal_eta (x ++ word_inverse x) = 1
  Proof.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: Words
amal_eta (x ++ word_inverse x) = 1
    induction x as [|x xs].
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
amal_eta (nil ++ word_inverse nil) = 1
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: H + K
xs: list (H + K)
IHxs: amal_eta (xs ++ word_inverse xs) = 1
amal_eta ((x :: xs) ++ word_inverse (x :: xs)) = 1
    1: reflexivity.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: H + K
xs: list (H + K)
IHxs: amal_eta (xs ++ word_inverse xs) = 1
amal_eta ((x :: xs) ++ word_inverse (x :: xs)) = 1
    destruct x as [h|k].
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
h: H
xs: list (H + K)
IHxs: amal_eta (xs ++ word_inverse xs) = 1
amal_eta ((inl h :: xs) ++ word_inverse (inl h :: xs)) = 1
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
k: K
xs: list (H + K)
IHxs: amal_eta (xs ++ word_inverse xs) = 1
amal_eta ((inr k :: xs) ++ word_inverse (inr k :: xs)) = 1
    +
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
h: H
xs: list (H + K)
IHxs: amal_eta (xs ++ word_inverse xs) = 1
amal_eta ((inl h :: xs) ++ word_inverse (inl h :: xs)) = 1 cbn.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
h: H
xs: list (H + K)
IHxs: amal_eta (xs ++ word_inverse xs) = 1
amal_eta (inl h :: xs ++ word_inverse xs ++ [inl h^]) = 1
      rewrite app_assoc.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
h: H
xs: list (H + K)
IHxs: amal_eta (xs ++ word_inverse xs) = 1
amal_eta (inl h :: (xs ++ word_inverse xs) ++ [inl h^]) = 1
      change (amal_eta ([inl h]) * amal_eta ((xs ++ word_inverse xs)) * amal_eta ([inl h^]) = mon_unit).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
h: H
xs: list (H + K)
IHxs: amal_eta (xs ++ word_inverse xs) = 1
amal_eta [inl h] * amal_eta (xs ++ word_inverse xs) * amal_eta [inl h^] = 1
      rewrite IHxs.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
h: H
xs: list (H + K)
IHxs: amal_eta (xs ++ word_inverse xs) = 1
amal_eta [inl h] * 1 * amal_eta [inl h^] = 1
      rewrite rightidentity_sgop_amal_type.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
h: H
xs: list (H + K)
IHxs: amal_eta (xs ++ word_inverse xs) = 1
amal_eta [inl h] * amal_eta [inl h^] = 1
      rewrite <- (app_nil (cons _ _)).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
h: H
xs: list (H + K)
IHxs: amal_eta (xs ++ word_inverse xs) = 1
amal_eta ([inl h] ++ nil) * amal_eta [inl h^] = 1
      change (amal_eta (([inl h] ++ [inl h^]) ++ nil) = mon_unit).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
h: H
xs: list (H + K)
IHxs: amal_eta (xs ++ word_inverse xs) = 1
amal_eta (([inl h] ++ [inl h^]) ++ nil) = 1
      rewrite <- app_assoc.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
h: H
xs: list (H + K)
IHxs: amal_eta (xs ++ word_inverse xs) = 1
amal_eta ([inl h] ++ [inl h^] ++ nil) = 1
      change (amal_eta (nil ++ [inl h] ++ [inl h^] ++ nil) = mon_unit).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
h: H
xs: list (H + K)
IHxs: amal_eta (xs ++ word_inverse xs) = 1
amal_eta (nil ++ [inl h] ++ [inl h^] ++ nil) = 1
      refine (amal_mu_H _ _ _ _ @ _).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
h: H
xs: list (H + K)
IHxs: amal_eta (xs ++ word_inverse xs) = 1
amal_eta (nil ++ [inl (h * h^)] ++ nil) = 1
      refine (_ @ _).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
h: H
xs: list (H + K)
IHxs: amal_eta (xs ++ word_inverse xs) = 1
amal_eta (nil ++ [inl (h * h^)] ++ nil) = ?Goal0
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
h: H
xs: list (H + K)
IHxs: amal_eta (xs ++ word_inverse xs) = 1
?Goal0 = 1
      {
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
h: H
xs: list (H + K)
IHxs: amal_eta (xs ++ word_inverse xs) = 1
amal_eta (nil ++ [inl (h * h^)] ++ nil) = ?Goal0 apply ap, ap.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
h: H
xs: list (H + K)
IHxs: amal_eta (xs ++ word_inverse xs) = 1
[inl (h * h^)] ++ nil = ?y
        rapply (ap (fun x => x ++ _)).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
h: H
xs: list (H + K)
IHxs: amal_eta (xs ++ word_inverse xs) = 1
[inl (h * h^)] = ?Goal1
        rapply (ap (fun x => [x])).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
h: H
xs: list (H + K)
IHxs: amal_eta (xs ++ word_inverse xs) = 1
inl (h * h^) = ?Goal1
        apply ap.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
h: H
xs: list (H + K)
IHxs: amal_eta (xs ++ word_inverse xs) = 1
h * h^ = ?y
        apply right_inverse. }
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
h: H
xs: list (H + K)
IHxs: amal_eta (xs ++ word_inverse xs) = 1
amal_eta (nil ++ [inl 1] ++ nil) = 1
      apply amal_omega_H.
    +
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
k: K
xs: list (H + K)
IHxs: amal_eta (xs ++ word_inverse xs) = 1
amal_eta ((inr k :: xs) ++ word_inverse (inr k :: xs)) = 1  cbn.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
k: K
xs: list (H + K)
IHxs: amal_eta (xs ++ word_inverse xs) = 1
amal_eta (inr k :: xs ++ word_inverse xs ++ [inr k^]) = 1
      rewrite app_assoc.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
k: K
xs: list (H + K)
IHxs: amal_eta (xs ++ word_inverse xs) = 1
amal_eta (inr k :: (xs ++ word_inverse xs) ++ [inr k^]) = 1
      change (amal_eta ([inr k]) * amal_eta ((xs ++ word_inverse xs)) * amal_eta ([inr k^]) = mon_unit).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
k: K
xs: list (H + K)
IHxs: amal_eta (xs ++ word_inverse xs) = 1
amal_eta [inr k] * amal_eta (xs ++ word_inverse xs) * amal_eta [inr k^] = 1
      rewrite IHxs.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
k: K
xs: list (H + K)
IHxs: amal_eta (xs ++ word_inverse xs) = 1
amal_eta [inr k] * 1 * amal_eta [inr k^] = 1
      rewrite rightidentity_sgop_amal_type.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
k: K
xs: list (H + K)
IHxs: amal_eta (xs ++ word_inverse xs) = 1
amal_eta [inr k] * amal_eta [inr k^] = 1
      rewrite <- (app_nil (cons _ _)).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
k: K
xs: list (H + K)
IHxs: amal_eta (xs ++ word_inverse xs) = 1
amal_eta ([inr k] ++ nil) * amal_eta [inr k^] = 1
      change (amal_eta (([inr k] ++ [inr k^]) ++ nil) = mon_unit).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
k: K
xs: list (H + K)
IHxs: amal_eta (xs ++ word_inverse xs) = 1
amal_eta (([inr k] ++ [inr k^]) ++ nil) = 1
      rewrite <- app_assoc.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
k: K
xs: list (H + K)
IHxs: amal_eta (xs ++ word_inverse xs) = 1
amal_eta ([inr k] ++ [inr k^] ++ nil) = 1
      change (amal_eta (nil ++ [inr k] ++ [inr k^] ++ nil) = mon_unit).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
k: K
xs: list (H + K)
IHxs: amal_eta (xs ++ word_inverse xs) = 1
amal_eta (nil ++ [inr k] ++ [inr k^] ++ nil) = 1
      refine (amal_mu_K _ _ _ _ @ _).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
k: K
xs: list (H + K)
IHxs: amal_eta (xs ++ word_inverse xs) = 1
amal_eta (nil ++ [inr (k * k^)] ++ nil) = 1
      refine (_ @ _).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
k: K
xs: list (H + K)
IHxs: amal_eta (xs ++ word_inverse xs) = 1
amal_eta (nil ++ [inr (k * k^)] ++ nil) = ?Goal
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
k: K
xs: list (H + K)
IHxs: amal_eta (xs ++ word_inverse xs) = 1
?Goal = 1
      {
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
k: K
xs: list (H + K)
IHxs: amal_eta (xs ++ word_inverse xs) = 1
amal_eta (nil ++ [inr (k * k^)] ++ nil) = ?Goal apply ap, ap.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
k: K
xs: list (H + K)
IHxs: amal_eta (xs ++ word_inverse xs) = 1
[inr (k * k^)] ++ nil = ?y
        rapply (ap (fun x => x ++ _)).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
k: K
xs: list (H + K)
IHxs: amal_eta (xs ++ word_inverse xs) = 1
[inr (k * k^)] = ?Goal0
        rapply (ap (fun x => [x])).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
k: K
xs: list (H + K)
IHxs: amal_eta (xs ++ word_inverse xs) = 1
inr (k * k^) = ?Goal0
        apply ap.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
k: K
xs: list (H + K)
IHxs: amal_eta (xs ++ word_inverse xs) = 1
k * k^ = ?y
        apply right_inverse. }
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
k: K
xs: list (H + K)
IHxs: amal_eta (xs ++ word_inverse xs) = 1
amal_eta (nil ++ [inr 1] ++ nil) = 1
      apply amal_omega_K.
  Defined.

  Local Instance leftinverse_sgop_amal_type : LeftInverse (.*.) (^) mon_unit.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
LeftInverse sg_op inv 1
  Proof.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
LeftInverse sg_op inv 1
    rapply amal_type_ind_hprop; intro x.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: Words
(amal_eta x)^ * amal_eta x = 1
    apply amal_eta_word_concat_Vw.
  Defined.

  Local Instance rightinverse_sgop_amal_type : RightInverse (.*.) (^) mon_unit.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
RightInverse sg_op inv 1
  Proof.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
RightInverse sg_op inv 1
    rapply amal_type_ind_hprop; intro x.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: Words
amal_eta x * (amal_eta x)^ = 1
    apply amal_eta_word_concat_wV.
  Defined.

  Definition AmalgamatedFreeProduct : Group.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
Group
  Proof.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
Group
    snapply (Build_Group amal_type sgop_amal_type); repeat split; exact _.
  Defined.

End AmalgamatedFreeProduct.

Arguments amal_eta {G H K f g} x.
Arguments amal_mu_H {G H K f g} x y.
Arguments amal_mu_K {G H K f g} x y.
Arguments amal_tau {G H K f g} x y z.
Arguments amal_omega_H {G H K f g} x y.
Arguments amal_omega_K {G H K f g} x y.

Section RecInd.

  Context {G H K : Group}
    {f : GroupHomomorphism G H} {g : GroupHomomorphism G K}.

  (** Using foldr. It's important that we use foldr as foldl is near impossible to reason about. *)
  Definition AmalgamatedFreeProduct_rec' (X : Group)
    (h : GroupHomomorphism H X) (k : GroupHomomorphism K X)
    (p : h o f == k o g)
    : AmalgamatedFreeProduct f g -> X.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
AmalgamatedFreeProduct f g -> X
  Proof.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
AmalgamatedFreeProduct f g -> X
    srapply amal_type_rec.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
Words -> X
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
forall (x y : Words) (h1 h2 : H),
?e (x ++ [inl h1, inl h2] ++ y) = ?e (x ++ [inl (h1 * h2)] ++ y)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
forall (x y : Words) (k1 k2 : K),
?e (x ++ [inr k1, inr k2] ++ y) = ?e (x ++ [inr (k1 * k2)] ++ y)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
forall (x y : Words) (z : G),
?e (x ++ [inl (f z)] ++ y) = ?e (x ++ [inr (g z)] ++ y)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
forall x y : Words, ?e (x ++ [inl 1] ++ y) = ?e (x ++ y)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
forall x y : Words, ?e (x ++ [inr 1] ++ y) = ?e (x ++ y)
    {
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
Words -> X intro w.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
w: Words
X
      refine (fold_right _ _ w).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
w: Words
H + K -> X -> X
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
w: Words
X
      {
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
w: Words
H + K -> X -> X intros [l|r] x.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
w: Words
l: H
x: X
X
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
w: Words
r: K
x: X
X
        +
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
w: Words
l: H
x: X
X exact (h l * x).
        +
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
w: Words
r: K
x: X
X exact (k r * x). }
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
w: Words
X
      exact mon_unit. }
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
forall (x y : Words) (h1 h2 : H),
(fun w : Words =>
 fold_right
   (fun X0 : H + K =>
    match X0 with
    | inl g0 => (fun (l : H) (x0 : X) => h l * x0) g0
    | inr g0 => (fun (r : K) (x0 : X) => k r * x0) g0
    end)
   1 w)
  (x ++ [inl h1, inl h2] ++ y) =
(fun w : Words =>
 fold_right
   (fun X0 : H + K =>
    match X0 with
    | inl g0 => (fun (l : H) (x0 : X) => h l * x0) g0
    | inr g0 => (fun (r : K) (x0 : X) => k r * x0) g0
    end)
   1 w)
  (x ++ [inl (h1 * h2)] ++ y)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
forall (x y : Words) (k1 k2 : K),
(fun w : Words =>
 fold_right
   (fun X0 : H + K =>
    match X0 with
    | inl g0 => (fun (l : H) (x0 : X) => h l * x0) g0
    | inr g0 => (fun (r : K) (x0 : X) => k r * x0) g0
    end)
   1 w)
  (x ++ [inr k1, inr k2] ++ y) =
(fun w : Words =>
 fold_right
   (fun X0 : H + K =>
    match X0 with
    | inl g0 => (fun (l : H) (x0 : X) => h l * x0) g0
    | inr g0 => (fun (r : K) (x0 : X) => k r * x0) g0
    end)
   1 w)
  (x ++ [inr (k1 * k2)] ++ y)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
forall (x y : Words) (z : G),
(fun w : Words =>
 fold_right
   (fun X0 : H + K =>
    match X0 with
    | inl g0 => (fun (l : H) (x0 : X) => h l * x0) g0
    | inr g0 => (fun (r : K) (x0 : X) => k r * x0) g0
    end)
   1 w)
  (x ++ [inl (f z)] ++ y) =
(fun w : Words =>
 fold_right
   (fun X0 : H + K =>
    match X0 with
    | inl g0 => (fun (l : H) (x0 : X) => h l * x0) g0
    | inr g0 => (fun (r : K) (x0 : X) => k r * x0) g0
    end)
   1 w)
  (x ++ [inr (g z)] ++ y)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
forall x y : Words,
(fun w : Words =>
 fold_right
   (fun X0 : H + K =>
    match X0 with
    | inl g0 => (fun (l : H) (x0 : X) => h l * x0) g0
    | inr g0 => (fun (r : K) (x0 : X) => k r * x0) g0
    end)
   1 w)
  (x ++ [inl 1] ++ y) =
(fun w : Words =>
 fold_right
   (fun X0 : H + K =>
    match X0 with
    | inl g0 => (fun (l : H) (x0 : X) => h l * x0) g0
    | inr g0 => (fun (r : K) (x0 : X) => k r * x0) g0
    end)
   1 w)
  (x ++ y)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
forall x y : Words,
(fun w : Words =>
 fold_right
   (fun X0 : H + K =>
    match X0 with
    | inl g0 => (fun (l : H) (x0 : X) => h l * x0) g0
    | inr g0 => (fun (r : K) (x0 : X) => k r * x0) g0
    end)
   1 w)
  (x ++ [inr 1] ++ y) =
(fun w : Words =>
 fold_right
   (fun X0 : H + K =>
    match X0 with
    | inl g0 => (fun (l : H) (x0 : X) => h l * x0) g0
    | inr g0 => (fun (r : K) (x0 : X) => k r * x0) g0
    end)
   1 w)
  (x ++ y)
    {
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
forall (x y : Words) (h1 h2 : H),
(fun w : Words =>
 fold_right
   (fun X0 : H + K =>
    match X0 with
    | inl g0 => (fun (l : H) (x0 : X) => h l * x0) g0
    | inr g0 => (fun (r : K) (x0 : X) => k r * x0) g0
    end)
   1 w)
  (x ++ [inl h1, inl h2] ++ y) =
(fun w : Words =>
 fold_right
   (fun X0 : H + K =>
    match X0 with
    | inl g0 => (fun (l : H) (x0 : X) => h l * x0) g0
    | inr g0 => (fun (r : K) (x0 : X) => k r * x0) g0
    end)
   1 w)
  (x ++ [inl (h1 * h2)] ++ y) intros x y h1 h2; hnf.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
x, y: Words
h1, h2: H
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  1 (x ++ [inl h1, inl h2] ++ y) =
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  1 (x ++ [inl (h1 * h2)] ++ y)
      rewrite ?fold_right_app.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
x, y: Words
h1, h2: H
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  (fold_right
     (fun X0 : H + K =>
      match X0 with
      | inl g0 => fun x0 : X => h g0 * x0
      | inr g0 => fun x0 : X => k g0 * x0
      end)
     (fold_right
        (fun X0 : H + K =>
         match X0 with
         | inl g0 => fun x0 : X => h g0 * x0
         | inr g0 => fun x0 : X => k g0 * x0
         end)
        1 y)
     [inl h1, inl h2])
  x =
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  (fold_right
     (fun X0 : H + K =>
      match X0 with
      | inl g0 => fun x0 : X => h g0 * x0
      | inr g0 => fun x0 : X => k g0 * x0
      end)
     (fold_right
        (fun X0 : H + K =>
         match X0 with
         | inl g0 => fun x0 : X => h g0 * x0
         | inr g0 => fun x0 : X => k g0 * x0
         end)
        1 y)
     [inl (h1 * h2)])
  x
      f_ap.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
x, y: Words
h1, h2: H
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  (fold_right
     (fun X0 : H + K =>
      match X0 with
      | inl g0 => fun x0 : X => h g0 * x0
      | inr g0 => fun x0 : X => k g0 * x0
      end)
     1 y)
  [inl h1, inl h2] =
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  (fold_right
     (fun X0 : H + K =>
      match X0 with
      | inl g0 => fun x0 : X => h g0 * x0
      | inr g0 => fun x0 : X => k g0 * x0
      end)
     1 y)
  [inl (h1 * h2)]
      simpl.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
x, y: Words
h1, h2: H
h h1 *
(h h2 *
 fold_right
   (fun X0 : H + K =>
    match X0 with
    | inl g0 => fun x0 : X => h g0 * x0
    | inr g0 => fun x0 : X => k g0 * x0
    end)
   1 y) =
h (h1 * h2) *
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  1 y
      rewrite simple_associativity.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
x, y: Words
h1, h2: H
h h1 * h h2 *
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  1 y =
h (h1 * h2) *
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  1 y
      f_ap.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
x, y: Words
h1, h2: H
h h1 * h h2 = h (h1 * h2)
      symmetry.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
x, y: Words
h1, h2: H
h (h1 * h2) = h h1 * h h2
      exact (grp_homo_op h h1 h2). }
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
forall (x y : Words) (k1 k2 : K),
(fun w : Words =>
 fold_right
   (fun X0 : H + K =>
    match X0 with
    | inl g0 => (fun (l : H) (x0 : X) => h l * x0) g0
    | inr g0 => (fun (r : K) (x0 : X) => k r * x0) g0
    end)
   1 w)
  (x ++ [inr k1, inr k2] ++ y) =
(fun w : Words =>
 fold_right
   (fun X0 : H + K =>
    match X0 with
    | inl g0 => (fun (l : H) (x0 : X) => h l * x0) g0
    | inr g0 => (fun (r : K) (x0 : X) => k r * x0) g0
    end)
   1 w)
  (x ++ [inr (k1 * k2)] ++ y)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
forall (x y : Words) (z : G),
(fun w : Words =>
 fold_right
   (fun X0 : H + K =>
    match X0 with
    | inl g0 => (fun (l : H) (x0 : X) => h l * x0) g0
    | inr g0 => (fun (r : K) (x0 : X) => k r * x0) g0
    end)
   1 w)
  (x ++ [inl (f z)] ++ y) =
(fun w : Words =>
 fold_right
   (fun X0 : H + K =>
    match X0 with
    | inl g0 => (fun (l : H) (x0 : X) => h l * x0) g0
    | inr g0 => (fun (r : K) (x0 : X) => k r * x0) g0
    end)
   1 w)
  (x ++ [inr (g z)] ++ y)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
forall x y : Words,
(fun w : Words =>
 fold_right
   (fun X0 : H + K =>
    match X0 with
    | inl g0 => (fun (l : H) (x0 : X) => h l * x0) g0
    | inr g0 => (fun (r : K) (x0 : X) => k r * x0) g0
    end)
   1 w)
  (x ++ [inl 1] ++ y) =
(fun w : Words =>
 fold_right
   (fun X0 : H + K =>
    match X0 with
    | inl g0 => (fun (l : H) (x0 : X) => h l * x0) g0
    | inr g0 => (fun (r : K) (x0 : X) => k r * x0) g0
    end)
   1 w)
  (x ++ y)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
forall x y : Words,
(fun w : Words =>
 fold_right
   (fun X0 : H + K =>
    match X0 with
    | inl g0 => (fun (l : H) (x0 : X) => h l * x0) g0
    | inr g0 => (fun (r : K) (x0 : X) => k r * x0) g0
    end)
   1 w)
  (x ++ [inr 1] ++ y) =
(fun w : Words =>
 fold_right
   (fun X0 : H + K =>
    match X0 with
    | inl g0 => (fun (l : H) (x0 : X) => h l * x0) g0
    | inr g0 => (fun (r : K) (x0 : X) => k r * x0) g0
    end)
   1 w)
  (x ++ y)
    {
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
forall (x y : Words) (k1 k2 : K),
(fun w : Words =>
 fold_right
   (fun X0 : H + K =>
    match X0 with
    | inl g0 => (fun (l : H) (x0 : X) => h l * x0) g0
    | inr g0 => (fun (r : K) (x0 : X) => k r * x0) g0
    end)
   1 w)
  (x ++ [inr k1, inr k2] ++ y) =
(fun w : Words =>
 fold_right
   (fun X0 : H + K =>
    match X0 with
    | inl g0 => (fun (l : H) (x0 : X) => h l * x0) g0
    | inr g0 => (fun (r : K) (x0 : X) => k r * x0) g0
    end)
   1 w)
  (x ++ [inr (k1 * k2)] ++ y) intros x y k1 k2; hnf.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
x, y: Words
k1, k2: K
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  1 (x ++ [inr k1, inr k2] ++ y) =
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  1 (x ++ [inr (k1 * k2)] ++ y)
      rewrite ?fold_right_app.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
x, y: Words
k1, k2: K
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  (fold_right
     (fun X0 : H + K =>
      match X0 with
      | inl g0 => fun x0 : X => h g0 * x0
      | inr g0 => fun x0 : X => k g0 * x0
      end)
     (fold_right
        (fun X0 : H + K =>
         match X0 with
         | inl g0 => fun x0 : X => h g0 * x0
         | inr g0 => fun x0 : X => k g0 * x0
         end)
        1 y)
     [inr k1, inr k2])
  x =
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  (fold_right
     (fun X0 : H + K =>
      match X0 with
      | inl g0 => fun x0 : X => h g0 * x0
      | inr g0 => fun x0 : X => k g0 * x0
      end)
     (fold_right
        (fun X0 : H + K =>
         match X0 with
         | inl g0 => fun x0 : X => h g0 * x0
         | inr g0 => fun x0 : X => k g0 * x0
         end)
        1 y)
     [inr (k1 * k2)])
  x
      f_ap.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
x, y: Words
k1, k2: K
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  (fold_right
     (fun X0 : H + K =>
      match X0 with
      | inl g0 => fun x0 : X => h g0 * x0
      | inr g0 => fun x0 : X => k g0 * x0
      end)
     1 y)
  [inr k1, inr k2] =
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  (fold_right
     (fun X0 : H + K =>
      match X0 with
      | inl g0 => fun x0 : X => h g0 * x0
      | inr g0 => fun x0 : X => k g0 * x0
      end)
     1 y)
  [inr (k1 * k2)]
      simpl.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
x, y: Words
k1, k2: K
k k1 *
(k k2 *
 fold_right
   (fun X0 : H + K =>
    match X0 with
    | inl g0 => fun x0 : X => h g0 * x0
    | inr g0 => fun x0 : X => k g0 * x0
    end)
   1 y) =
k (k1 * k2) *
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  1 y
      rewrite simple_associativity.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
x, y: Words
k1, k2: K
k k1 * k k2 *
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  1 y =
k (k1 * k2) *
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  1 y
      f_ap.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
x, y: Words
k1, k2: K
k k1 * k k2 = k (k1 * k2)
      symmetry.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
x, y: Words
k1, k2: K
k (k1 * k2) = k k1 * k k2
      exact (grp_homo_op k k1 k2). }
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
forall (x y : Words) (z : G),
(fun w : Words =>
 fold_right
   (fun X0 : H + K =>
    match X0 with
    | inl g0 => (fun (l : H) (x0 : X) => h l * x0) g0
    | inr g0 => (fun (r : K) (x0 : X) => k r * x0) g0
    end)
   1 w)
  (x ++ [inl (f z)] ++ y) =
(fun w : Words =>
 fold_right
   (fun X0 : H + K =>
    match X0 with
    | inl g0 => (fun (l : H) (x0 : X) => h l * x0) g0
    | inr g0 => (fun (r : K) (x0 : X) => k r * x0) g0
    end)
   1 w)
  (x ++ [inr (g z)] ++ y)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
forall x y : Words,
(fun w : Words =>
 fold_right
   (fun X0 : H + K =>
    match X0 with
    | inl g0 => (fun (l : H) (x0 : X) => h l * x0) g0
    | inr g0 => (fun (r : K) (x0 : X) => k r * x0) g0
    end)
   1 w)
  (x ++ [inl 1] ++ y) =
(fun w : Words =>
 fold_right
   (fun X0 : H + K =>
    match X0 with
    | inl g0 => (fun (l : H) (x0 : X) => h l * x0) g0
    | inr g0 => (fun (r : K) (x0 : X) => k r * x0) g0
    end)
   1 w)
  (x ++ y)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
forall x y : Words,
(fun w : Words =>
 fold_right
   (fun X0 : H + K =>
    match X0 with
    | inl g0 => (fun (l : H) (x0 : X) => h l * x0) g0
    | inr g0 => (fun (r : K) (x0 : X) => k r * x0) g0
    end)
   1 w)
  (x ++ [inr 1] ++ y) =
(fun w : Words =>
 fold_right
   (fun X0 : H + K =>
    match X0 with
    | inl g0 => (fun (l : H) (x0 : X) => h l * x0) g0
    | inr g0 => (fun (r : K) (x0 : X) => k r * x0) g0
    end)
   1 w)
  (x ++ y)
    {
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
forall (x y : Words) (z : G),
(fun w : Words =>
 fold_right
   (fun X0 : H + K =>
    match X0 with
    | inl g0 => (fun (l : H) (x0 : X) => h l * x0) g0
    | inr g0 => (fun (r : K) (x0 : X) => k r * x0) g0
    end)
   1 w)
  (x ++ [inl (f z)] ++ y) =
(fun w : Words =>
 fold_right
   (fun X0 : H + K =>
    match X0 with
    | inl g0 => (fun (l : H) (x0 : X) => h l * x0) g0
    | inr g0 => (fun (r : K) (x0 : X) => k r * x0) g0
    end)
   1 w)
  (x ++ [inr (g z)] ++ y) intros x y z; hnf.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
x, y: Words
z: G
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  1 (x ++ [inl (f z)] ++ y) =
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  1 (x ++ [inr (g z)] ++ y)
      rewrite ?fold_right_app.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
x, y: Words
z: G
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  (fold_right
     (fun X0 : H + K =>
      match X0 with
      | inl g0 => fun x0 : X => h g0 * x0
      | inr g0 => fun x0 : X => k g0 * x0
      end)
     (fold_right
        (fun X0 : H + K =>
         match X0 with
         | inl g0 => fun x0 : X => h g0 * x0
         | inr g0 => fun x0 : X => k g0 * x0
         end)
        1 y)
     [inl (f z)])
  x =
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  (fold_right
     (fun X0 : H + K =>
      match X0 with
      | inl g0 => fun x0 : X => h g0 * x0
      | inr g0 => fun x0 : X => k g0 * x0
      end)
     (fold_right
        (fun X0 : H + K =>
         match X0 with
         | inl g0 => fun x0 : X => h g0 * x0
         | inr g0 => fun x0 : X => k g0 * x0
         end)
        1 y)
     [inr (g z)])
  x
      f_ap; simpl; f_ap. }
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
forall x y : Words,
(fun w : Words =>
 fold_right
   (fun X0 : H + K =>
    match X0 with
    | inl g0 => (fun (l : H) (x0 : X) => h l * x0) g0
    | inr g0 => (fun (r : K) (x0 : X) => k r * x0) g0
    end)
   1 w)
  (x ++ [inl 1] ++ y) =
(fun w : Words =>
 fold_right
   (fun X0 : H + K =>
    match X0 with
    | inl g0 => (fun (l : H) (x0 : X) => h l * x0) g0
    | inr g0 => (fun (r : K) (x0 : X) => k r * x0) g0
    end)
   1 w)
  (x ++ y)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
forall x y : Words,
(fun w : Words =>
 fold_right
   (fun X0 : H + K =>
    match X0 with
    | inl g0 => (fun (l : H) (x0 : X) => h l * x0) g0
    | inr g0 => (fun (r : K) (x0 : X) => k r * x0) g0
    end)
   1 w)
  (x ++ [inr 1] ++ y) =
(fun w : Words =>
 fold_right
   (fun X0 : H + K =>
    match X0 with
    | inl g0 => (fun (l : H) (x0 : X) => h l * x0) g0
    | inr g0 => (fun (r : K) (x0 : X) => k r * x0) g0
    end)
   1 w)
  (x ++ y)
    {
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
forall x y : Words,
(fun w : Words =>
 fold_right
   (fun X0 : H + K =>
    match X0 with
    | inl g0 => (fun (l : H) (x0 : X) => h l * x0) g0
    | inr g0 => (fun (r : K) (x0 : X) => k r * x0) g0
    end)
   1 w)
  (x ++ [inl 1] ++ y) =
(fun w : Words =>
 fold_right
   (fun X0 : H + K =>
    match X0 with
    | inl g0 => (fun (l : H) (x0 : X) => h l * x0) g0
    | inr g0 => (fun (r : K) (x0 : X) => k r * x0) g0
    end)
   1 w)
  (x ++ y) intros x y; hnf.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
x, y: Words
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  1 (x ++ [inl 1] ++ y) =
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  1 (x ++ y)
      rewrite ?fold_right_app.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
x, y: Words
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  (fold_right
     (fun X0 : H + K =>
      match X0 with
      | inl g0 => fun x0 : X => h g0 * x0
      | inr g0 => fun x0 : X => k g0 * x0
      end)
     (fold_right
        (fun X0 : H + K =>
         match X0 with
         | inl g0 => fun x0 : X => h g0 * x0
         | inr g0 => fun x0 : X => k g0 * x0
         end)
        1 y)
     [inl 1])
  x =
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  (fold_right
     (fun X0 : H + K =>
      match X0 with
      | inl g0 => fun x0 : X => h g0 * x0
      | inr g0 => fun x0 : X => k g0 * x0
      end)
     1 y)
  x
      f_ap.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
x, y: Words
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  (fold_right
     (fun X0 : H + K =>
      match X0 with
      | inl g0 => fun x0 : X => h g0 * x0
      | inr g0 => fun x0 : X => k g0 * x0
      end)
     1 y)
  [inl 1] =
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  1 y simpl.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
x, y: Words
h 1 *
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  1 y =
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  1 y rewrite grp_homo_unit.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
x, y: Words
1 *
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  1 y =
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  1 y
      rapply left_identity. }
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
forall x y : Words,
(fun w : Words =>
 fold_right
   (fun X0 : H + K =>
    match X0 with
    | inl g0 => (fun (l : H) (x0 : X) => h l * x0) g0
    | inr g0 => (fun (r : K) (x0 : X) => k r * x0) g0
    end)
   1 w)
  (x ++ [inr 1] ++ y) =
(fun w : Words =>
 fold_right
   (fun X0 : H + K =>
    match X0 with
    | inl g0 => (fun (l : H) (x0 : X) => h l * x0) g0
    | inr g0 => (fun (r : K) (x0 : X) => k r * x0) g0
    end)
   1 w)
  (x ++ y)
    {
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
forall x y : Words,
(fun w : Words =>
 fold_right
   (fun X0 : H + K =>
    match X0 with
    | inl g0 => (fun (l : H) (x0 : X) => h l * x0) g0
    | inr g0 => (fun (r : K) (x0 : X) => k r * x0) g0
    end)
   1 w)
  (x ++ [inr 1] ++ y) =
(fun w : Words =>
 fold_right
   (fun X0 : H + K =>
    match X0 with
    | inl g0 => (fun (l : H) (x0 : X) => h l * x0) g0
    | inr g0 => (fun (r : K) (x0 : X) => k r * x0) g0
    end)
   1 w)
  (x ++ y) intros x y; hnf.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
x, y: Words
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  1 (x ++ [inr 1] ++ y) =
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  1 (x ++ y)
      rewrite ?fold_right_app.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
x, y: Words
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  (fold_right
     (fun X0 : H + K =>
      match X0 with
      | inl g0 => fun x0 : X => h g0 * x0
      | inr g0 => fun x0 : X => k g0 * x0
      end)
     (fold_right
        (fun X0 : H + K =>
         match X0 with
         | inl g0 => fun x0 : X => h g0 * x0
         | inr g0 => fun x0 : X => k g0 * x0
         end)
        1 y)
     [inr 1])
  x =
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  (fold_right
     (fun X0 : H + K =>
      match X0 with
      | inl g0 => fun x0 : X => h g0 * x0
      | inr g0 => fun x0 : X => k g0 * x0
      end)
     1 y)
  x
      f_ap.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
x, y: Words
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  (fold_right
     (fun X0 : H + K =>
      match X0 with
      | inl g0 => fun x0 : X => h g0 * x0
      | inr g0 => fun x0 : X => k g0 * x0
      end)
     1 y)
  [inr 1] =
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  1 y simpl.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
x, y: Words
k 1 *
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  1 y =
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  1 y rewrite grp_homo_unit.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
x, y: Words
1 *
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  1 y =
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  1 y
      rapply left_identity. }
  Defined.

  Local Instance issemigrouppreserving_AmalgamatedFreeProduct_rec'
    (X : Group) (h : GroupHomomorphism H X) (k : GroupHomomorphism K X)
    (p : h o f == k o g)
    : IsSemiGroupPreserving (AmalgamatedFreeProduct_rec' X h k p).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
IsSemiGroupPreserving (AmalgamatedFreeProduct_rec' X h k p)
  Proof.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
IsSemiGroupPreserving (AmalgamatedFreeProduct_rec' X h k p)
    intros x; srapply amal_type_ind_hprop; intro y; revert x;
    srapply amal_type_ind_hprop; intro x; simpl.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
y, x: Words
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  1 (x ++ y) =
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  1 x *
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  1 y
    rewrite fold_right_app.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
y, x: Words
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  (fold_right
     (fun X0 : H + K =>
      match X0 with
      | inl g0 => fun x0 : X => h g0 * x0
      | inr g0 => fun x0 : X => k g0 * x0
      end)
     1 y)
  x =
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  1 x *
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  1 y
    set (s := (fold_right
     (fun X0 : H + K => match X0 with
                        | inl l => fun x0 : X => h l * x0
                        | inr r => fun x0 : X => k r * x0
                        end) mon_unit y)).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
y, x: Words
s:= fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl l => fun x0 : X => h l * x0
   | inr r => fun x0 : X => k r * x0
   end)
  1 y: X
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  s x =
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  1 x *
s
    induction x as [|a x].
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
y: Words
s:= fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl l => fun x0 : X => h l * x0
   | inr r => fun x0 : X => k r * x0
   end)
  1 y: X
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x : X => h g0 * x
   | inr g0 => fun x : X => k g0 * x
   end)
  s nil =
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x : X => h g0 * x
   | inr g0 => fun x : X => k g0 * x
   end)
  1 nil *
s
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
y: Words
a: H + K
x: list (H + K)
s:= fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl l => fun x0 : X => h l * x0
   | inr r => fun x0 : X => k r * x0
   end)
  1 y: X
IHx: fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  s x =
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  1 x *
s
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  s (a :: x) =
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  1 (a :: x) *
s
    1: symmetry; apply left_identity.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
y: Words
a: H + K
x: list (H + K)
s:= fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl l => fun x0 : X => h l * x0
   | inr r => fun x0 : X => k r * x0
   end)
  1 y: X
IHx: fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  s x =
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  1 x *
s
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  s (a :: x) =
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  1 (a :: x) *
s
    simpl.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
y: Words
a: H + K
x: list (H + K)
s:= fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl l => fun x0 : X => h l * x0
   | inr r => fun x0 : X => k r * x0
   end)
  1 y: X
IHx: fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  s x =
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  1 x *
s
match a with
| inl g0 => fun x0 : X => h g0 * x0
| inr g0 => fun x0 : X => k g0 * x0
end
  (fold_right
     (fun X0 : H + K =>
      match X0 with
      | inl g0 => fun x0 : X => h g0 * x0
      | inr g0 => fun x0 : X => k g0 * x0
      end)
     s x) =
match a with
| inl g0 => fun x0 : X => h g0 * x0
| inr g0 => fun x0 : X => k g0 * x0
end
  (fold_right
     (fun X0 : H + K =>
      match X0 with
      | inl g0 => fun x0 : X => h g0 * x0
      | inr g0 => fun x0 : X => k g0 * x0
      end)
     1 x) *
s
    rewrite IHx.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: GroupHomomorphism H X
k: GroupHomomorphism K X
p: h o f == k o g
y: Words
a: H + K
x: list (H + K)
s:= fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl l => fun x0 : X => h l * x0
   | inr r => fun x0 : X => k r * x0
   end)
  1 y: X
IHx: fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  s x =
fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => h g0 * x0
   | inr g0 => fun x0 : X => k g0 * x0
   end)
  1 x *
s
match a with
| inl g0 => fun x0 : X => h g0 * x0
| inr g0 => fun x0 : X => k g0 * x0
end
  (fold_right
     (fun X0 : H + K =>
      match X0 with
      | inl g0 => fun x0 : X => h g0 * x0
      | inr g0 => fun x0 : X => k g0 * x0
      end)
     1 x *
   s) =
match a with
| inl g0 => fun x0 : X => h g0 * x0
| inr g0 => fun x0 : X => k g0 * x0
end
  (fold_right
     (fun X0 : H + K =>
      match X0 with
      | inl g0 => fun x0 : X => h g0 * x0
      | inr g0 => fun x0 : X => k g0 * x0
      end)
     1 x) *
s
    destruct a; apply simple_associativity.
  Qed.

  Definition AmalgamatedFreeProduct_rec (X : Group)
    (h : H $-> X) (k : K $-> X)
    (p : h $o f $== k $o g)
    : AmalgamatedFreeProduct f g $-> X.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: H $-> X
k: K $-> X
p: h $o f $== k $o g
AmalgamatedFreeProduct f g $-> X
  Proof.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: H $-> X
k: K $-> X
p: h $o f $== k $o g
AmalgamatedFreeProduct f g $-> X
    snapply Build_GroupHomomorphism.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: H $-> X
k: K $-> X
p: h $o f $== k $o g
AmalgamatedFreeProduct f g -> X
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: H $-> X
k: K $-> X
p: h $o f $== k $o g
IsSemiGroupPreserving ?grp_homo_map
    1: srapply (AmalgamatedFreeProduct_rec' X h k p).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
X: Group
h: H $-> X
k: K $-> X
p: h $o f $== k $o g
IsSemiGroupPreserving (AmalgamatedFreeProduct_rec' X h k p)
    exact _.
  Defined.

  Definition amal_inl : H $-> AmalgamatedFreeProduct f g.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H $-> AmalgamatedFreeProduct f g
  Proof.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H $-> AmalgamatedFreeProduct f g
    snapply Build_GroupHomomorphism.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H -> AmalgamatedFreeProduct f g
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
IsSemiGroupPreserving ?grp_homo_map
    {
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H -> AmalgamatedFreeProduct f g intro x.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: H
AmalgamatedFreeProduct f g
      exact (amal_eta [inl x]). }
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
IsSemiGroupPreserving (fun x : H => amal_eta [inl x])
    intros x y.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: H
amal_eta [inl (x * y)] = amal_eta [inl x] * amal_eta [inl y]
    rewrite <- (app_nil [inl (x * y)]).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: H
amal_eta ([inl (x * y)] ++ nil) = amal_eta [inl x] * amal_eta [inl y]
    rewrite <- (amal_mu_H nil nil x y).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: H
amal_eta (nil ++ [inl x, inl y] ++ nil) = amal_eta [inl x] * amal_eta [inl y]
    rewrite app_nil.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: H
amal_eta (nil ++ [inl x, inl y]) = amal_eta [inl x] * amal_eta [inl y]
    reflexivity.
  Defined.

  Definition amal_inr : K $-> AmalgamatedFreeProduct f g.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
K $-> AmalgamatedFreeProduct f g
  Proof.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
K $-> AmalgamatedFreeProduct f g
    snapply Build_GroupHomomorphism.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
K -> AmalgamatedFreeProduct f g
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
IsSemiGroupPreserving ?grp_homo_map
    {
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
K -> AmalgamatedFreeProduct f g intro x.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x: K
AmalgamatedFreeProduct f g
      exact (amal_eta [inr x]). }
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
IsSemiGroupPreserving (fun x : K => amal_eta [inr x])
    intros x y.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: K
amal_eta [inr (x * y)] = amal_eta [inr x] * amal_eta [inr y]
    rewrite <- (app_nil [inr (x * y)]).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: K
amal_eta ([inr (x * y)] ++ nil) = amal_eta [inr x] * amal_eta [inr y]
    rewrite <- (amal_mu_K nil nil x y).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: K
amal_eta (nil ++ [inr x, inr y] ++ nil) = amal_eta [inr x] * amal_eta [inr y]
    rewrite app_nil.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
x, y: K
amal_eta (nil ++ [inr x, inr y]) = amal_eta [inr x] * amal_eta [inr y]
    reflexivity.
  Defined.
  
  Definition amal_glue : amal_inl $o f $== amal_inr $o g.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
amal_inl $o f $== amal_inr $o g
  Proof.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
amal_inl $o f $== amal_inr $o g
    hnf; apply (amal_tau nil nil).
  Defined.

  Theorem equiv_amalgamatedfreeproduct_rec `{Funext} (X : Group)
    : {h : H $-> X & {k : K $-> X & h $o f $== k $o g }}
      <~> (AmalgamatedFreeProduct f g $-> X).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H0: Funext
X: Group
{h : H $-> X & {k : K $-> X & h $o f $== k $o g}} <~>
(AmalgamatedFreeProduct f g $-> X)
  Proof.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H0: Funext
X: Group
{h : H $-> X & {k : K $-> X & h $o f $== k $o g}} <~>
(AmalgamatedFreeProduct f g $-> X)
    snapply equiv_adjointify.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H0: Funext
X: Group
{h : H $-> X & {k : K $-> X & h $o f $== k $o g}} ->
AmalgamatedFreeProduct f g $-> X
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H0: Funext
X: Group
(AmalgamatedFreeProduct f g $-> X) ->
{h : H $-> X & {k : K $-> X & h $o f $== k $o g}}
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H0: Funext
X: Group
?f o ?g == idmap
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H0: Funext
X: Group
?g o ?f == idmap
    1: intros [h [k p]]; exact (AmalgamatedFreeProduct_rec X h k p).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H0: Funext
X: Group
(AmalgamatedFreeProduct f g $-> X) ->
{h : H $-> X & {k : K $-> X & h $o f $== k $o g}}
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H0: Funext
X: Group
(fun X0 : {h : H $-> X & {k : K $-> X & h $o f $== k $o g}} =>
 (fun (h : H $-> X) (proj2 : {k : K $-> X & h $o f $== k $o g}) =>
  (fun (k : K $-> X) (p : h $o f $== k $o g) =>
   AmalgamatedFreeProduct_rec X h k p) proj2.1 proj2.2) X0.1 X0.2)
o ?g == idmap
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H0: Funext
X: Group
?g
o (fun X0 : {h : H $-> X & {k : K $-> X & h $o f $== k $o g}} =>
   (fun (h : H $-> X) (proj2 : {k : K $-> X & h $o f $== k $o g}) =>
    (fun (k : K $-> X) (p : h $o f $== k $o g) =>
     AmalgamatedFreeProduct_rec X h k p) proj2.1 proj2.2) X0.1 X0.2) ==
idmap
    {
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H0: Funext
X: Group
(AmalgamatedFreeProduct f g $-> X) ->
{h : H $-> X & {k : K $-> X & h $o f $== k $o g}} intros r.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H0: Funext
X: Group
r: AmalgamatedFreeProduct f g $-> X
{h : H $-> X & {k : K $-> X & h $o f $== k $o g}}
      exists (grp_homo_compose r amal_inl).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H0: Funext
X: Group
r: AmalgamatedFreeProduct f g $-> X
{k : K $-> X & grp_homo_compose r amal_inl $o f $== k $o g}
      exists (grp_homo_compose r amal_inr).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H0: Funext
X: Group
r: AmalgamatedFreeProduct f g $-> X
grp_homo_compose r amal_inl $o f $== grp_homo_compose r amal_inr $o g
      intro x.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H0: Funext
X: Group
r: AmalgamatedFreeProduct f g $-> X
x: G
(grp_homo_compose r amal_inl $o f) x = (grp_homo_compose r amal_inr $o g) x
      apply (ap r).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H0: Funext
X: Group
r: AmalgamatedFreeProduct f g $-> X
x: G
amal_inl (f x) = amal_inr (g x)
      simpl.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H0: Funext
X: Group
r: AmalgamatedFreeProduct f g $-> X
x: G
amal_eta [inl (f x)] = amal_eta [inr (g x)]
      rewrite <- (app_nil [inl (f x)]).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H0: Funext
X: Group
r: AmalgamatedFreeProduct f g $-> X
x: G
amal_eta ([inl (f x)] ++ nil) = amal_eta [inr (g x)]
      rewrite <- (app_nil [inr (g x)]).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H0: Funext
X: Group
r: AmalgamatedFreeProduct f g $-> X
x: G
amal_eta ([inl (f x)] ++ nil) = amal_eta ([inr (g x)] ++ nil)
      exact (amal_tau nil nil x). }
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H0: Funext
X: Group
(fun X0 : {h : H $-> X & {k : K $-> X & h $o f $== k $o g}} =>
 (fun (h : H $-> X) (proj2 : {k : K $-> X & h $o f $== k $o g}) =>
  (fun (k : K $-> X) (p : h $o f $== k $o g) =>
   AmalgamatedFreeProduct_rec X h k p) proj2.1 proj2.2) X0.1 X0.2)
o (fun r : AmalgamatedFreeProduct f g $-> X =>
   (grp_homo_compose r amal_inl; grp_homo_compose r amal_inr;
   (fun x : G =>
    ap r
      (internal_paths_rew
         (fun l : list (H + K) => amal_eta l = amal_eta [inr (g x)])
         (internal_paths_rew
            (fun l : list (H + K) =>
             amal_eta ([inl (f x)] ++ nil) = amal_eta l)
            (amal_tau nil nil x) (app_nil [inr (g x)]))
         (app_nil [inl (f x)])
       :
       amal_inl (f x) = amal_inr (g x)))
   :
   grp_homo_compose r amal_inl $o f $== grp_homo_compose r amal_inr $o g)) ==
idmap
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H0: Funext
X: Group
(fun r : AmalgamatedFreeProduct f g $-> X =>
 (grp_homo_compose r amal_inl; grp_homo_compose r amal_inr;
 (fun x : G =>
  ap r
    (internal_paths_rew
       (fun l : list (H + K) => amal_eta l = amal_eta [inr (g x)])
       (internal_paths_rew
          (fun l : list (H + K) => amal_eta ([inl (f x)] ++ nil) = amal_eta l)
          (amal_tau nil nil x) (app_nil [inr (g x)]))
       (app_nil [inl (f x)])
     :
     amal_inl (f x) = amal_inr (g x)))
 :
 grp_homo_compose r amal_inl $o f $== grp_homo_compose r amal_inr $o g))
o (fun X0 : {h : H $-> X & {k : K $-> X & h $o f $== k $o g}} =>
   (fun (h : H $-> X) (proj2 : {k : K $-> X & h $o f $== k $o g}) =>
    (fun (k : K $-> X) (p : h $o f $== k $o g) =>
     AmalgamatedFreeProduct_rec X h k p) proj2.1 proj2.2) X0.1 X0.2) ==
idmap
    {
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H0: Funext
X: Group
(fun X0 : {h : H $-> X & {k : K $-> X & h $o f $== k $o g}} =>
 (fun (h : H $-> X) (proj2 : {k : K $-> X & h $o f $== k $o g}) =>
  (fun (k : K $-> X) (p : h $o f $== k $o g) =>
   AmalgamatedFreeProduct_rec X h k p) proj2.1 proj2.2) X0.1 X0.2)
o (fun r : AmalgamatedFreeProduct f g $-> X =>
   (grp_homo_compose r amal_inl; grp_homo_compose r amal_inr;
   (fun x : G =>
    ap r
      (internal_paths_rew
         (fun l : list (H + K) => amal_eta l = amal_eta [inr (g x)])
         (internal_paths_rew
            (fun l : list (H + K) =>
             amal_eta ([inl (f x)] ++ nil) = amal_eta l)
            (amal_tau nil nil x) (app_nil [inr (g x)]))
         (app_nil [inl (f x)])
       :
       amal_inl (f x) = amal_inr (g x)))
   :
   grp_homo_compose r amal_inl $o f $== grp_homo_compose r amal_inr $o g)) ==
idmap intros r.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H0: Funext
X: Group
r: AmalgamatedFreeProduct f g $-> X
AmalgamatedFreeProduct_rec X (grp_homo_compose r amal_inl)
  (grp_homo_compose r amal_inr)
  (fun x : G =>
   ap r
     (internal_paths_rew
        (fun l : list (H + K) => amal_eta l = amal_eta [inr (g x)])
        (internal_paths_rew
           (fun l : list (H + K) =>
            amal_eta ([inl (f x)] ++ nil) = amal_eta l)
           (amal_tau nil nil x) (app_nil [inr (g x)]))
        (app_nil [inl (f x)]))) =
r
      apply equiv_path_grouphomomorphism.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H0: Funext
X: Group
r: AmalgamatedFreeProduct f g $-> X
AmalgamatedFreeProduct_rec X (grp_homo_compose r amal_inl)
  (grp_homo_compose r amal_inr)
  (fun x : G =>
   ap r
     (internal_paths_rew
        (fun l : list (H + K) => amal_eta l = amal_eta [inr (g x)])
        (internal_paths_rew
           (fun l : list (H + K) =>
            amal_eta ([inl (f x)] ++ nil) = amal_eta l)
           (amal_tau nil nil x) (app_nil [inr (g x)]))
        (app_nil [inl (f x)]))) ==
r
      srapply amal_type_ind_hprop.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H0: Funext
X: Group
r: AmalgamatedFreeProduct f g $-> X
forall w : Words,
(fun x : amal_type f g =>
 AmalgamatedFreeProduct_rec X (grp_homo_compose r amal_inl)
   (grp_homo_compose r amal_inr)
   (fun x0 : G =>
    ap r
      (internal_paths_rew
         (fun l : list (H + K) => amal_eta l = amal_eta [inr (g x0)])
         (internal_paths_rew
            (fun l : list (H + K) =>
             amal_eta ([inl (f x0)] ++ nil) = amal_eta l)
            (amal_tau nil nil x0) (app_nil [inr (g x0)]))
         (app_nil [inl (f x0)])))
   x =
 r x) (amal_eta w)
      intro x.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H0: Funext
X: Group
r: AmalgamatedFreeProduct f g $-> X
x: Words
(fun x0 : amal_type f g =>
 AmalgamatedFreeProduct_rec X (grp_homo_compose r amal_inl)
   (grp_homo_compose r amal_inr)
   (fun x1 : G =>
    ap r
      (internal_paths_rew
         (fun l : list (H + K) => amal_eta l = amal_eta [inr (g x1)])
         (internal_paths_rew
            (fun l : list (H + K) =>
             amal_eta ([inl (f x1)] ++ nil) = amal_eta l)
            (amal_tau nil nil x1) (app_nil [inr (g x1)]))
         (app_nil [inl (f x1)])))
   x0 =
 r x0) (amal_eta x)
      induction x as [|a x].
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H0: Funext
X: Group
r: AmalgamatedFreeProduct f g $-> X
AmalgamatedFreeProduct_rec X (grp_homo_compose r amal_inl)
  (grp_homo_compose r amal_inr)
  (fun x : G =>
   ap r
     (internal_paths_rew
        (fun l : list (H + K) => amal_eta l = amal_eta [inr (g x)])
        (internal_paths_rew
           (fun l : list (H + K) =>
            amal_eta ([inl (f x)] ++ nil) = amal_eta l)
           (amal_tau nil nil x) (app_nil [inr (g x)]))
        (app_nil [inl (f x)])))
  (amal_eta nil) =
r (amal_eta nil)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H0: Funext
X: Group
r: AmalgamatedFreeProduct f g $-> X
a: H + K
x: list (H + K)
IHx: AmalgamatedFreeProduct_rec X (grp_homo_compose r amal_inl)
  (grp_homo_compose r amal_inr)
  (fun x0 : G =>
   ap r
     (internal_paths_rew
        (fun l : list (H + K) => amal_eta l = amal_eta [inr (g x0)])
        (internal_paths_rew
           (fun l : list (H + K) =>
            amal_eta ([inl (f x0)] ++ nil) = amal_eta l)
           (amal_tau nil nil x0) (app_nil [inr (g x0)]))
        (app_nil [inl (f x0)])))
  (amal_eta x) =
r (amal_eta x)
AmalgamatedFreeProduct_rec X (grp_homo_compose r amal_inl)
  (grp_homo_compose r amal_inr)
  (fun x0 : G =>
   ap r
     (internal_paths_rew
        (fun l : list (H + K) => amal_eta l = amal_eta [inr (g x0)])
        (internal_paths_rew
           (fun l : list (H + K) =>
            amal_eta ([inl (f x0)] ++ nil) = amal_eta l)
           (amal_tau nil nil x0) (app_nil [inr (g x0)]))
        (app_nil [inl (f x0)])))
  (amal_eta (a :: x)) =
r (amal_eta (a :: x))
      1: symmetry; exact (grp_homo_unit r).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H0: Funext
X: Group
r: AmalgamatedFreeProduct f g $-> X
a: H + K
x: list (H + K)
IHx: AmalgamatedFreeProduct_rec X (grp_homo_compose r amal_inl)
  (grp_homo_compose r amal_inr)
  (fun x0 : G =>
   ap r
     (internal_paths_rew
        (fun l : list (H + K) => amal_eta l = amal_eta [inr (g x0)])
        (internal_paths_rew
           (fun l : list (H + K) =>
            amal_eta ([inl (f x0)] ++ nil) = amal_eta l)
           (amal_tau nil nil x0) (app_nil [inr (g x0)]))
        (app_nil [inl (f x0)])))
  (amal_eta x) =
r (amal_eta x)
AmalgamatedFreeProduct_rec X (grp_homo_compose r amal_inl)
  (grp_homo_compose r amal_inr)
  (fun x0 : G =>
   ap r
     (internal_paths_rew
        (fun l : list (H + K) => amal_eta l = amal_eta [inr (g x0)])
        (internal_paths_rew
           (fun l : list (H + K) =>
            amal_eta ([inl (f x0)] ++ nil) = amal_eta l)
           (amal_tau nil nil x0) (app_nil [inr (g x0)]))
        (app_nil [inl (f x0)])))
  (amal_eta (a :: x)) =
r (amal_eta (a :: x))
      simpl in *.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H0: Funext
X: Group
r: GroupHomomorphism (AmalgamatedFreeProduct f g) X
a: H + K
x: list (H + K)
IHx: fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => r (amal_eta [inl g0]) * x0
   | inr g0 => fun x0 : X => r (amal_eta [inr g0]) * x0
   end)
  1 x =
r (amal_eta x)
match a with
| inl g0 => fun x0 : X => r (amal_eta [inl g0]) * x0
| inr g0 => fun x0 : X => r (amal_eta [inr g0]) * x0
end
  (fold_right
     (fun X0 : H + K =>
      match X0 with
      | inl g0 => fun x0 : X => r (amal_eta [inl g0]) * x0
      | inr g0 => fun x0 : X => r (amal_eta [inr g0]) * x0
      end)
     1 x) =
r (amal_eta (a :: x))
      rewrite IHx.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H0: Funext
X: Group
r: GroupHomomorphism (AmalgamatedFreeProduct f g) X
a: H + K
x: list (H + K)
IHx: fold_right
  (fun X0 : H + K =>
   match X0 with
   | inl g0 => fun x0 : X => r (amal_eta [inl g0]) * x0
   | inr g0 => fun x0 : X => r (amal_eta [inr g0]) * x0
   end)
  1 x =
r (amal_eta x)
match a with
| inl g0 => fun x0 : X => r (amal_eta [inl g0]) * x0
| inr g0 => fun x0 : X => r (amal_eta [inr g0]) * x0
end (r (amal_eta x)) = r (amal_eta (a :: x))
      destruct a; symmetry;
      rapply (grp_homo_op r (amal_eta [_]) (amal_eta x)). }
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H0: Funext
X: Group
(fun r : AmalgamatedFreeProduct f g $-> X =>
 (grp_homo_compose r amal_inl; grp_homo_compose r amal_inr;
 (fun x : G =>
  ap r
    (internal_paths_rew
       (fun l : list (H + K) => amal_eta l = amal_eta [inr (g x)])
       (internal_paths_rew
          (fun l : list (H + K) => amal_eta ([inl (f x)] ++ nil) = amal_eta l)
          (amal_tau nil nil x) (app_nil [inr (g x)]))
       (app_nil [inl (f x)])
     :
     amal_inl (f x) = amal_inr (g x)))
 :
 grp_homo_compose r amal_inl $o f $== grp_homo_compose r amal_inr $o g))
o (fun X0 : {h : H $-> X & {k : K $-> X & h $o f $== k $o g}} =>
   (fun (h : H $-> X) (proj2 : {k : K $-> X & h $o f $== k $o g}) =>
    (fun (k : K $-> X) (p : h $o f $== k $o g) =>
     AmalgamatedFreeProduct_rec X h k p) proj2.1 proj2.2) X0.1 X0.2) ==
idmap
    intro hkp.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H0: Funext
X: Group
hkp: {h : H $-> X & {k : K $-> X & h $o f $== k $o g}}
(grp_homo_compose (AmalgamatedFreeProduct_rec X hkp.1 (hkp.2).1 (hkp.2).2)
   amal_inl;
grp_homo_compose (AmalgamatedFreeProduct_rec X hkp.1 (hkp.2).1 (hkp.2).2)
  amal_inr;
fun x : G =>
ap (AmalgamatedFreeProduct_rec X hkp.1 (hkp.2).1 (hkp.2).2)
  (internal_paths_rew
     (fun l : list (H + K) => amal_eta l = amal_eta [inr (g x)])
     (internal_paths_rew
        (fun l : list (H + K) => amal_eta ([inl (f x)] ++ nil) = amal_eta l)
        (amal_tau nil nil x) (app_nil [inr (g x)]))
     (app_nil [inl (f x)]))) =
hkp
    simpl.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H0: Funext
X: Group
hkp: {h : H $-> X & {k : K $-> X & h $o f $== k $o g}}
(grp_homo_compose (AmalgamatedFreeProduct_rec X hkp.1 (hkp.2).1 (hkp.2).2)
   amal_inl;
grp_homo_compose (AmalgamatedFreeProduct_rec X hkp.1 (hkp.2).1 (hkp.2).2)
  amal_inr;
fun x : G =>
ap (AmalgamatedFreeProduct_rec' X hkp.1 (hkp.2).1 (hkp.2).2)
  (amal_tau nil nil x)) =
hkp
    tapply (equiv_ap' (equiv_sigma_prod
      (fun hk : (H $-> X) * (K $-> X)
        => fst hk o f == snd hk o g)) _ _)^-1%equiv.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H0: Funext
X: Group
hkp: {h : H $-> X & {k : K $-> X & h $o f $== k $o g}}
equiv_sigma_prod
  (fun hk : (H $-> X) * (K $-> X) =>
   (fun x : G => fst hk (f x)) == (fun x : G => snd hk (g x)))
  (grp_homo_compose (AmalgamatedFreeProduct_rec X hkp.1 (hkp.2).1 (hkp.2).2)
     amal_inl;
  grp_homo_compose (AmalgamatedFreeProduct_rec X hkp.1 (hkp.2).1 (hkp.2).2)
    amal_inr;
  fun x : G =>
  ap (AmalgamatedFreeProduct_rec' X hkp.1 (hkp.2).1 (hkp.2).2)
    (amal_tau nil nil x)) =
equiv_sigma_prod
  (fun hk : (H $-> X) * (K $-> X) =>
   (fun x : G => fst hk (f x)) == (fun x : G => snd hk (g x)))
  hkp
    rapply path_sigma_hprop.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H0: Funext
X: Group
hkp: {h : H $-> X & {k : K $-> X & h $o f $== k $o g}}
(equiv_sigma_prod
   (fun hk : (H $-> X) * (K $-> X) =>
    (fun x : G => fst hk (f x)) == (fun x : G => snd hk (g x)))
   (grp_homo_compose (AmalgamatedFreeProduct_rec X hkp.1 (hkp.2).1 (hkp.2).2)
      amal_inl;
   grp_homo_compose (AmalgamatedFreeProduct_rec X hkp.1 (hkp.2).1 (hkp.2).2)
     amal_inr;
   fun x : G =>
   ap (AmalgamatedFreeProduct_rec' X hkp.1 (hkp.2).1 (hkp.2).2)
     (amal_tau nil nil x))).1 =
(equiv_sigma_prod
   (fun hk : (H $-> X) * (K $-> X) =>
    (fun x : G => fst hk (f x)) == (fun x : G => snd hk (g x)))
   hkp).1
    destruct hkp as [h [k p]].
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H0: Funext
X: Group
h: H $-> X
k: K $-> X
p: h $o f $== k $o g
(equiv_sigma_prod
   (fun hk : (H $-> X) * (K $-> X) =>
    (fun x : G => fst hk (f x)) == (fun x : G => snd hk (g x)))
   (grp_homo_compose (AmalgamatedFreeProduct_rec X h k p) amal_inl;
   grp_homo_compose (AmalgamatedFreeProduct_rec X h k p) amal_inr;
   fun x : G => ap (AmalgamatedFreeProduct_rec' X h k p) (amal_tau nil nil x))).1 =
(equiv_sigma_prod
   (fun hk : (H $-> X) * (K $-> X) =>
    (fun x : G => fst hk (f x)) == (fun x : G => snd hk (g x)))
   (h; k; p)).1
    apply path_prod; cbn;
    apply equiv_path_grouphomomorphism;
    intro; simpl; rapply right_identity.
  Defined.
  
  Definition amalgamatedfreeproduct_ind_hprop (P : AmalgamatedFreeProduct f g -> Type)
    `{forall x, IsHProp (P x)}
    (l : forall a, P (amal_inl a)) (r : forall b, P (amal_inr b))
    (Hop : forall x y, P x -> P y -> P (x * y))
    : forall x, P x.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: AmalgamatedFreeProduct f g -> Type
H0: forall x : AmalgamatedFreeProduct f g, IsHProp (P x)
l: forall a : H, P (amal_inl a)
r: forall b : K, P (amal_inr b)
Hop: forall x y : AmalgamatedFreeProduct f g, P x -> P y -> P (x * y)
forall x : AmalgamatedFreeProduct f g, P x
  Proof.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: AmalgamatedFreeProduct f g -> Type
H0: forall x : AmalgamatedFreeProduct f g, IsHProp (P x)
l: forall a : H, P (amal_inl a)
r: forall b : K, P (amal_inr b)
Hop: forall x y : AmalgamatedFreeProduct f g, P x -> P y -> P (x * y)
forall x : AmalgamatedFreeProduct f g, P x
    rapply amal_type_ind_hprop.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: AmalgamatedFreeProduct f g -> Type
H0: forall x : AmalgamatedFreeProduct f g, IsHProp (P x)
l: forall a : H, P (amal_inl a)
r: forall b : K, P (amal_inr b)
Hop: forall x y : AmalgamatedFreeProduct f g, P x -> P y -> P (x * y)
forall w : Words, P (amal_eta w)
    intros w.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: AmalgamatedFreeProduct f g -> Type
H0: forall x : AmalgamatedFreeProduct f g, IsHProp (P x)
l: forall a : H, P (amal_inl a)
r: forall b : K, P (amal_inr b)
Hop: forall x y : AmalgamatedFreeProduct f g, P x -> P y -> P (x * y)
w: Words
P (amal_eta w)
    simple_list_induction w a w IH.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: AmalgamatedFreeProduct f g -> Type
H0: forall x : AmalgamatedFreeProduct f g, IsHProp (P x)
l: forall a : H, P (amal_inl a)
r: forall b : K, P (amal_inr b)
Hop: forall x y : AmalgamatedFreeProduct f g, P x -> P y -> P (x * y)
P (amal_eta nil)
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: AmalgamatedFreeProduct f g -> Type
H0: forall x : AmalgamatedFreeProduct f g, IsHProp (P x)
l: forall a0 : H, P (amal_inl a0)
r: forall b : K, P (amal_inr b)
Hop: forall x y : AmalgamatedFreeProduct f g, P x -> P y -> P (x * y)
w: list (H + K)
IH: P (amal_eta w)
a: H + K
P (amal_eta (a :: w))
    -
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: AmalgamatedFreeProduct f g -> Type
H0: forall x : AmalgamatedFreeProduct f g, IsHProp (P x)
l: forall a : H, P (amal_inl a)
r: forall b : K, P (amal_inr b)
Hop: forall x y : AmalgamatedFreeProduct f g, P x -> P y -> P (x * y)
P (amal_eta nil) rewrite <- (amal_omega_H nil nil).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: AmalgamatedFreeProduct f g -> Type
H0: forall x : AmalgamatedFreeProduct f g, IsHProp (P x)
l: forall a : H, P (amal_inl a)
r: forall b : K, P (amal_inr b)
Hop: forall x y : AmalgamatedFreeProduct f g, P x -> P y -> P (x * y)
P (amal_eta (nil ++ [inl 1] ++ nil))
      apply l.
    -
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: AmalgamatedFreeProduct f g -> Type
H0: forall x : AmalgamatedFreeProduct f g, IsHProp (P x)
l: forall a0 : H, P (amal_inl a0)
r: forall b : K, P (amal_inr b)
Hop: forall x y : AmalgamatedFreeProduct f g, P x -> P y -> P (x * y)
w: list (H + K)
IH: P (amal_eta w)
a: H + K
P (amal_eta (a :: w)) destruct a as [a|b].
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: AmalgamatedFreeProduct f g -> Type
H0: forall x : AmalgamatedFreeProduct f g, IsHProp (P x)
l: forall a0 : H, P (amal_inl a0)
r: forall b : K, P (amal_inr b)
Hop: forall x y : AmalgamatedFreeProduct f g, P x -> P y -> P (x * y)
w: list (H + K)
IH: P (amal_eta w)
a: H
P (amal_eta (inl a :: w))
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: AmalgamatedFreeProduct f g -> Type
H0: forall x : AmalgamatedFreeProduct f g, IsHProp (P x)
l: forall a : H, P (amal_inl a)
r: forall b0 : K, P (amal_inr b0)
Hop: forall x y : AmalgamatedFreeProduct f g, P x -> P y -> P (x * y)
w: list (H + K)
IH: P (amal_eta w)
b: K
P (amal_eta (inr b :: w))
      +
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: AmalgamatedFreeProduct f g -> Type
H0: forall x : AmalgamatedFreeProduct f g, IsHProp (P x)
l: forall a0 : H, P (amal_inl a0)
r: forall b : K, P (amal_inr b)
Hop: forall x y : AmalgamatedFreeProduct f g, P x -> P y -> P (x * y)
w: list (H + K)
IH: P (amal_eta w)
a: H
P (amal_eta (inl a :: w)) change (P (amal_inl a * amal_eta w)).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: AmalgamatedFreeProduct f g -> Type
H0: forall x : AmalgamatedFreeProduct f g, IsHProp (P x)
l: forall a0 : H, P (amal_inl a0)
r: forall b : K, P (amal_inr b)
Hop: forall x y : AmalgamatedFreeProduct f g, P x -> P y -> P (x * y)
w: list (H + K)
IH: P (amal_eta w)
a: H
P (amal_inl a * amal_eta w)
        by apply Hop.
      +
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: AmalgamatedFreeProduct f g -> Type
H0: forall x : AmalgamatedFreeProduct f g, IsHProp (P x)
l: forall a : H, P (amal_inl a)
r: forall b0 : K, P (amal_inr b0)
Hop: forall x y : AmalgamatedFreeProduct f g, P x -> P y -> P (x * y)
w: list (H + K)
IH: P (amal_eta w)
b: K
P (amal_eta (inr b :: w)) change (P (amal_inr b * amal_eta w)).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: AmalgamatedFreeProduct f g -> Type
H0: forall x : AmalgamatedFreeProduct f g, IsHProp (P x)
l: forall a : H, P (amal_inl a)
r: forall b0 : K, P (amal_inr b0)
Hop: forall x y : AmalgamatedFreeProduct f g, P x -> P y -> P (x * y)
w: list (H + K)
IH: P (amal_eta w)
b: K
P (amal_inr b * amal_eta w)
        by apply Hop.
  Defined.

  Definition amalgamatedfreeproduct_ind_homotopy {P : Group}
    {k k' : AmalgamatedFreeProduct f g $-> P}
    (l : k $o amal_inl $== k' $o amal_inl)
    (r : k $o amal_inr $== k' $o amal_inr)
    : k $== k'.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: Group
k, k': AmalgamatedFreeProduct f g $-> P
l: k $o amal_inl $== k' $o amal_inl
r: k $o amal_inr $== k' $o amal_inr
k $== k'
  Proof.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: Group
k, k': AmalgamatedFreeProduct f g $-> P
l: k $o amal_inl $== k' $o amal_inl
r: k $o amal_inr $== k' $o amal_inr
k $== k'
    rapply (amalgamatedfreeproduct_ind_hprop _ l r).
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
P: Group
k, k': AmalgamatedFreeProduct f g $-> P
l: k $o amal_inl $== k' $o amal_inl
r: k $o amal_inr $== k' $o amal_inr
forall x y : AmalgamatedFreeProduct f g,
k x = k' x -> k y = k' y -> k (x * y) = k' (x * y)
    intros x y; napply grp_homo_op_agree.
  Defined.

  Definition equiv_amalgamatedfreeproduct_ind_homotopy `{Funext} {P : Group}
    (k k' : AmalgamatedFreeProduct f g $-> P)
    : (k $o amal_inl $== k' $o amal_inl) * (k $o amal_inr $== k' $o amal_inr)
      <~> k $== k'.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H0: Funext
P: Group
k, k': AmalgamatedFreeProduct f g $-> P
(k $o amal_inl $== k' $o amal_inl) * (k $o amal_inr $== k' $o amal_inr) <~>
k $== k'
  Proof.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H0: Funext
P: Group
k, k': AmalgamatedFreeProduct f g $-> P
(k $o amal_inl $== k' $o amal_inl) * (k $o amal_inr $== k' $o amal_inr) <~>
k $== k'
    rapply equiv_iff_hprop.
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H0: Funext
P: Group
k, k': AmalgamatedFreeProduct f g $-> P
(k $o amal_inl $== k' $o amal_inl) * (k $o amal_inr $== k' $o amal_inr) ->
k $== k'
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H0: Funext
P: Group
k, k': AmalgamatedFreeProduct f g $-> P
k $== k' ->
(k $o amal_inl $== k' $o amal_inl) * (k $o amal_inr $== k' $o amal_inr)
    -
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H0: Funext
P: Group
k, k': AmalgamatedFreeProduct f g $-> P
(k $o amal_inl $== k' $o amal_inl) * (k $o amal_inr $== k' $o amal_inr) ->
k $== k' exact (uncurry amalgamatedfreeproduct_ind_homotopy).
    -
G, H, K: Group
f: GroupHomomorphism G H
g: GroupHomomorphism G K
H0: Funext
P: Group
k, k': AmalgamatedFreeProduct f g $-> P
k $== k' ->
(k $o amal_inl $== k' $o amal_inl) * (k $o amal_inr $== k' $o amal_inr) intros p; split; exact (p $@R _).
  Defined.

End RecInd.

Definition FreeProduct (G H : Group) : Group
  := AmalgamatedFreeProduct (grp_trivial_rec G) (grp_trivial_rec H).

Definition freeproduct_inl {G H : Group} : GroupHomomorphism G (FreeProduct G H)
  := amal_inl.

Definition freeproduct_inr {G H : Group} : GroupHomomorphism H (FreeProduct G H)
  := amal_inr.

Definition freeproduct_ind_hprop {G H} (P : FreeProduct G H -> Type)
  `{forall x, IsHProp (P x)}
  (l : forall g, P (freeproduct_inl g))
  (r : forall h, P (freeproduct_inr h))
  (Hop : forall x y, P x -> P y -> P (x * y))
  : forall x, P x
  := amalgamatedfreeproduct_ind_hprop P l r Hop.
(* The above is slow, ~0.15s. *)

Definition freeproduct_ind_homotopy {G H K : Group}
  {f f' : FreeProduct G H $-> K}
  (l : f $o freeproduct_inl $== f' $o freeproduct_inl)
  (r : f $o freeproduct_inr $== f' $o freeproduct_inr)
  : f $== f'
  := amalgamatedfreeproduct_ind_homotopy l r.

Definition equiv_freeproduct_ind_homotopy {Funext : Funext} {G H K : Group}
  (f f' : FreeProduct G H $-> K)
  : (f $o freeproduct_inl $== f' $o freeproduct_inl)
    * (f $o freeproduct_inr $== f' $o freeproduct_inr)
    <~> f $== f'
  := equiv_amalgamatedfreeproduct_ind_homotopy _ _.

Definition FreeProduct_rec {G H K : Group} (f : G $-> K) (g : H $-> K)
  : FreeProduct G H $-> K.
G, H, K: Group
f: G $-> K
g: H $-> K
FreeProduct G H $-> K
Proof.
G, H, K: Group
f: G $-> K
g: H $-> K
FreeProduct G H $-> K
  srapply (AmalgamatedFreeProduct_rec _ f g).
G, H, K: Group
f: G $-> K
g: H $-> K
f $o grp_trivial_rec G $== g $o grp_trivial_rec H
  intros [].
G, H, K: Group
f: G $-> K
g: H $-> K
(f $o grp_trivial_rec G) tt = (g $o grp_trivial_rec H) tt
  exact (grp_homo_unit f @ (grp_homo_unit g)^).
Defined.

Definition freeproduct_rec_beta_inl {G H K : Group}
  (f : G $-> K) (g : H $-> K)
  : FreeProduct_rec f g $o freeproduct_inl $== f
  := fun x => right_identity (f x).

Definition freeproduct_rec_beta_inr {G H K : Group}
  (f : G $-> K) (g : H $-> K)
  : FreeProduct_rec f g $o freeproduct_inr $== g
  := fun x => right_identity (g x).

Definition equiv_freeproduct_rec `{funext : Funext} (G H K : Group)
  : (GroupHomomorphism G K) * (GroupHomomorphism H K)
  <~> GroupHomomorphism (FreeProduct G H) K.
funext: Funext
G, H, K: Group
GroupHomomorphism G K * GroupHomomorphism H K <~>
GroupHomomorphism (FreeProduct G H) K
Proof.
funext: Funext
G, H, K: Group
GroupHomomorphism G K * GroupHomomorphism H K <~>
GroupHomomorphism (FreeProduct G H) K
  refine (equiv_amalgamatedfreeproduct_rec K oE _^-1).
funext: Funext
G, H, K: Group
{h : G $-> K &
{k : H $-> K & h $o grp_trivial_rec G $== k $o grp_trivial_rec H}} <~>
GroupHomomorphism G K * GroupHomomorphism H K
  refine (equiv_sigma_prod0 _ _ oE equiv_functor_sigma_id (fun _ => equiv_sigma_contr _)).
funext: Funext
G, H, K: Group
y: G $-> K
forall a : H $-> K, Contr (y $o grp_trivial_rec G $== a $o grp_trivial_rec H)
  intros f.
funext: Funext
G, H, K: Group
y: G $-> K
f: H $-> K
Contr (y $o grp_trivial_rec G $== f $o grp_trivial_rec H)
  rapply contr_forall.
funext: Funext
G, H, K: Group
y: G $-> K
f: H $-> K
forall a : grp_trivial,
Contr ((y $o grp_trivial_rec G) a = (f $o grp_trivial_rec H) a)
  intros []; rapply contr_inhabited_hprop.
funext: Funext
G, H, K: Group
y: G $-> K
f: H $-> K
(y $o grp_trivial_rec G) tt = (f $o grp_trivial_rec H) tt
  exact (grp_homo_unit _ @ (grp_homo_unit _)^).
Defined.

(** The free product is the coproduct in the category of groups. *)
Instance hasbinarycoproducts : HasBinaryCoproducts Group.
HasBinaryCoproducts Group
Proof.
HasBinaryCoproducts Group
  intros G H.
G, H: Group
BinaryCoproduct G H
  snapply Build_BinaryCoproduct.
G, H: Group
Group
G, H: Group
G $-> ?cat_coprod
G, H: Group
H $-> ?cat_coprod
G, H: Group
forall z : Group, (G $-> z) -> (H $-> z) -> ?cat_coprod $-> z
G, H: Group
forall (z : Group) (f : G $-> z) (g : H $-> z),
?cat_coprod_rec z f g $o ?cat_inl $== f
G, H: Group
forall (z : Group) (f : G $-> z) (g : H $-> z),
?cat_coprod_rec z f g $o ?cat_inr $== g
G, H: Group
forall (z : Group) (f g : ?cat_coprod $-> z),
f $o ?cat_inl $== g $o ?cat_inl -> f $o ?cat_inr $== g $o ?cat_inr -> f $== g
  -
G, H: Group
Group exact (FreeProduct G H).
  -
G, H: Group
G $-> FreeProduct G H exact freeproduct_inl.
  -
G, H: Group
H $-> FreeProduct G H exact freeproduct_inr.
  -
G, H: Group
forall z : Group, (G $-> z) -> (H $-> z) -> FreeProduct G H $-> z intros Z; exact FreeProduct_rec.
  -
G, H: Group
forall (z : Group) (f : G $-> z) (g : H $-> z),
(fun Z : Group => FreeProduct_rec) z f g $o freeproduct_inl $== f intros; apply freeproduct_rec_beta_inl.
  -
G, H: Group
forall (z : Group) (f : G $-> z) (g : H $-> z),
(fun Z : Group => FreeProduct_rec) z f g $o freeproduct_inr $== g intros; apply freeproduct_rec_beta_inr.
  -
G, H: Group
forall (z : Group) (f g : FreeProduct G H $-> z),
f $o freeproduct_inl $== g $o freeproduct_inl ->
f $o freeproduct_inr $== g $o freeproduct_inr -> f $== g intros Z f g p q.
G, H, Z: Group
f, g: FreeProduct G H $-> Z
p: f $o freeproduct_inl $== g $o freeproduct_inl
q: f $o freeproduct_inr $== g $o freeproduct_inr
f $== g
    by snapply freeproduct_ind_homotopy.
Defined.