l3lab/ntp-mathlib huggingface dataset:
private theorem Cofix.bisim_aux {α : TypeVec n} (r : Cofix F α → Cofix F α → Prop) (h' : ∀ x, r x x)
    (h : ∀ x y, r x y →
      appendFun id (Quot.mk r) <$$> Cofix.dest x = appendFun id (Quot.mk r) <$$> Cofix.dest y) :
    ∀ x y, r x y → x = y := by
  intro x
  rcases x; clear x; rename M (P F) α => x;
  intro y
  rcases y; clear y; rename M (P F) α => y;
  intro rxy
  apply Quot.sound
  let r' := fun x y => r (Quot.mk _ x) (Quot.mk _ y)
  have hr' : r' = fun x y => r (Quot.mk _ x) (Quot.mk _ y) := rfl
  have : IsPrecongr r' := by
    intro a b r'ab
    have h₀ :
      appendFun id (Quot.mk r ∘ Quot.mk Mcongr) <$$> MvQPF.abs (M.dest q.P a) =
        appendFun id (Quot.mk r ∘ Quot.mk Mcongr) <$$> MvQPF.abs (M.dest q.P b) :=
      by rw [appendFun_comp_id, comp_map, comp_map]; exact h _ _ r'ab
    have h₁ : ∀ u v : q.P.M α, Mcongr u v → Quot.mk r' u = Quot.mk r' v := by
      intro u v cuv
      apply Quot.sound
      dsimp [hr']
      rw [Quot.sound cuv]
      apply h'
    

Proof state:
n : ℕ
F : TypeVec.{u} (n + 1) → Type u
mvf : MvFunctor F
q : MvQPF F
α : TypeVec.{u} n
r : Cofix F α → Cofix F α → Prop
h' : ∀ (x : Cofix F α), r x x
h : ∀ (x y : Cofix F α), r x y → (TypeVec.id ::: Quot.mk r) <$$> dest x = (TypeVec.id ::: Quot.mk r) <$$> dest y
x y : M (P F) α
rxy : r (Quot.mk Mcongr x) (Quot.mk Mcongr y)
r' : M (P F) α → M (P F) α → Prop := fun x y => r (Quot.mk Mcongr x) (Quot.mk Mcongr y)
hr' : r' = fun x y => r (Quot.mk Mcongr x) (Quot.mk Mcongr y)
a b : M (P F) α
r'ab : r' a b
h₀ :
  (TypeVec.id ::: Quot.mk r ∘ Quot.mk Mcongr) <$$> MvQPF.abs (M.dest (P F) a) =
    (TypeVec.id ::: Quot.mk r ∘ Quot.mk Mcongr) <$$> MvQPF.abs (M.dest (P F) b)
h₁ : ∀ (u v : M (P F) α), Mcongr u v → Quot.mk r' u = Quot.mk r' v
⊢ MvQPF.abs ((TypeVec.id ::: Quot.mk r') <$$> M.dest (P F) a) =
    MvQPF.abs ((TypeVec.id ::: Quot.mk r') <$$> M.dest (P F) b)

Next tactic:
let f : Quot r → Quot r' :=
      Quot.lift (Quot.lift (Quot.mk r') h₁)
        (by
          intro c
          apply Quot.inductionOn
            (motive := fun c =>
              ∀b, r c b → Quot.lift (Quot.mk r') h₁ c = Quot.lift (Quot.mk r') h₁ b) c
          clear c
          intro c d
          apply Quot.inductionOn
            (motive := fun d => r (Quot.mk Mcongr c) d →
              Quot.lift (Quot.mk r') h₁ (Quot.mk Mcongr c) = Quot.lift (Quot.mk r') h₁ d) d
          clear d
          intro d rcd; apply Quot.sound; apply rcd)
private theorem Cofix.bisim_aux {α : TypeVec n} (r : Cofix F α → Cofix F α → Prop) (h' : ∀ x, r x x)
    (h : ∀ x y, r x y →
      appendFun id (Quot.mk r) <$$> Cofix.dest x = appendFun id (Quot.mk r) <$$> Cofix.dest y) :
    ∀ x y, r x y → x = y := by
  intro x
  rcases x; clear x; rename M (P F) α => x;
  intro y
  rcases y; clear y; rename M (P F) α => y;
  intro rxy
  apply Quot.sound
  let r' := fun x y => r (Quot.mk _ x) (Quot.mk _ y)
  have hr' : r' = fun x y => r (Quot.mk _ x) (Quot.mk _ y) := rfl
  have : IsPrecongr r' := by
    intro a b r'ab
    have h₀ :
      appendFun id (Quot.mk r ∘ Quot.mk Mcongr) <$$> MvQPF.abs (M.dest q.P a) =
        appendFun id (Quot.mk r ∘ Quot.mk Mcongr) <$$> MvQPF.abs (M.dest q.P b) :=
      by rw [appendFun_comp_id, comp_map, comp_map]; exact h _ _ r'ab
    have h₁ : ∀ u v : q.P.M α, Mcongr u v → Quot.mk r' u = Quot.mk r' v := by
      intro u v cuv
      apply Quot.sound
      dsimp [hr']
      rw [Quot.sound cuv]
      apply h'
    let f : Quot r → Quot r' :=
      Quot.lift (Quot.lift (Quot.mk r') h₁)
        (by
          

Proof state:
n : ℕ
F : TypeVec.{u} (n + 1) → Type u
mvf : MvFunctor F
q : MvQPF F
α : TypeVec.{u} n
r : Cofix F α → Cofix F α → Prop
h' : ∀ (x : Cofix F α), r x x
h : ∀ (x y : Cofix F α), r x y → (TypeVec.id ::: Quot.mk r) <$$> dest x = (TypeVec.id ::: Quot.mk r) <$$> dest y
x y : M (P F) α
rxy : r (Quot.mk Mcongr x) (Quot.mk Mcongr y)
r' : M (P F) α → M (P F) α → Prop := fun x y => r (Quot.mk Mcongr x) (Quot.mk Mcongr y)
hr' : r' = fun x y => r (Quot.mk Mcongr x) (Quot.mk Mcongr y)
a b : M (P F) α
r'ab : r' a b
h₀ :
  (TypeVec.id ::: Quot.mk r ∘ Quot.mk Mcongr) <$$> MvQPF.abs (M.dest (P F) a) =
    (TypeVec.id ::: Quot.mk r ∘ Quot.mk Mcongr) <$$> MvQPF.abs (M.dest (P F) b)
h₁ : ∀ (u v : M (P F) α), Mcongr u v → Quot.mk r' u = Quot.mk r' v
⊢ ∀ (a b : Cofix F α), r a b → Quot.lift (Quot.mk r') h₁ a = Quot.lift (Quot.mk r') h₁ b

Next tactic:
intro c
private theorem Cofix.bisim_aux {α : TypeVec n} (r : Cofix F α → Cofix F α → Prop) (h' : ∀ x, r x x)
    (h : ∀ x y, r x y →
      appendFun id (Quot.mk r) <$$> Cofix.dest x = appendFun id (Quot.mk r) <$$> Cofix.dest y) :
    ∀ x y, r x y → x = y := by
  intro x
  rcases x; clear x; rename M (P F) α => x;
  intro y
  rcases y; clear y; rename M (P F) α => y;
  intro rxy
  apply Quot.sound
  let r' := fun x y => r (Quot.mk _ x) (Quot.mk _ y)
  have hr' : r' = fun x y => r (Quot.mk _ x) (Quot.mk _ y) := rfl
  have : IsPrecongr r' := by
    intro a b r'ab
    have h₀ :
      appendFun id (Quot.mk r ∘ Quot.mk Mcongr) <$$> MvQPF.abs (M.dest q.P a) =
        appendFun id (Quot.mk r ∘ Quot.mk Mcongr) <$$> MvQPF.abs (M.dest q.P b) :=
      by rw [appendFun_comp_id, comp_map, comp_map]; exact h _ _ r'ab
    have h₁ : ∀ u v : q.P.M α, Mcongr u v → Quot.mk r' u = Quot.mk r' v := by
      intro u v cuv
      apply Quot.sound
      dsimp [hr']
      rw [Quot.sound cuv]
      apply h'
    let f : Quot r → Quot r' :=
      Quot.lift (Quot.lift (Quot.mk r') h₁)
        (by
          intro c
          

Proof state:
n : ℕ
F : TypeVec.{u} (n + 1) → Type u
mvf : MvFunctor F
q : MvQPF F
α : TypeVec.{u} n
r : Cofix F α → Cofix F α → Prop
h' : ∀ (x : Cofix F α), r x x
h : ∀ (x y : Cofix F α), r x y → (TypeVec.id ::: Quot.mk r) <$$> dest x = (TypeVec.id ::: Quot.mk r) <$$> dest y
x y : M (P F) α
rxy : r (Quot.mk Mcongr x) (Quot.mk Mcongr y)
r' : M (P F) α → M (P F) α → Prop := fun x y => r (Quot.mk Mcongr x) (Quot.mk Mcongr y)
hr' : r' = fun x y => r (Quot.mk Mcongr x) (Quot.mk Mcongr y)
a b : M (P F) α
r'ab : r' a b
h₀ :
  (TypeVec.id ::: Quot.mk r ∘ Quot.mk Mcongr) <$$> MvQPF.abs (M.dest (P F) a) =
    (TypeVec.id ::: Quot.mk r ∘ Quot.mk Mcongr) <$$> MvQPF.abs (M.dest (P F) b)
h₁ : ∀ (u v : M (P F) α), Mcongr u v → Quot.mk r' u = Quot.mk r' v
c : Cofix F α
⊢ ∀ (b : Cofix F α), r c b → Quot.lift (Quot.mk r') h₁ c = Quot.lift (Quot.mk r') h₁ b

Next tactic:
apply Quot.inductionOn
            (motive := fun c =>
              ∀b, r c b → Quot.lift (Quot.mk r') h₁ c = Quot.lift (Quot.mk r') h₁ b) c
private theorem Cofix.bisim_aux {α : TypeVec n} (r : Cofix F α → Cofix F α → Prop) (h' : ∀ x, r x x)
    (h : ∀ x y, r x y →
      appendFun id (Quot.mk r) <$$> Cofix.dest x = appendFun id (Quot.mk r) <$$> Cofix.dest y) :
    ∀ x y, r x y → x = y := by
  intro x
  rcases x; clear x; rename M (P F) α => x;
  intro y
  rcases y; clear y; rename M (P F) α => y;
  intro rxy
  apply Quot.sound
  let r' := fun x y => r (Quot.mk _ x) (Quot.mk _ y)
  have hr' : r' = fun x y => r (Quot.mk _ x) (Quot.mk _ y) := rfl
  have : IsPrecongr r' := by
    intro a b r'ab
    have h₀ :
      appendFun id (Quot.mk r ∘ Quot.mk Mcongr) <$$> MvQPF.abs (M.dest q.P a) =
        appendFun id (Quot.mk r ∘ Quot.mk Mcongr) <$$> MvQPF.abs (M.dest q.P b) :=
      by rw [appendFun_comp_id, comp_map, comp_map]; exact h _ _ r'ab
    have h₁ : ∀ u v : q.P.M α, Mcongr u v → Quot.mk r' u = Quot.mk r' v := by
      intro u v cuv
      apply Quot.sound
      dsimp [hr']
      rw [Quot.sound cuv]
      apply h'
    let f : Quot r → Quot r' :=
      Quot.lift (Quot.lift (Quot.mk r') h₁)
        (by
          intro c
          apply Quot.inductionOn
            (motive := fun c =>
              ∀b, r c b → Quot.lift (Quot.mk r') h₁ c = Quot.lift (Quot.mk r') h₁ b) c
          

Proof state:
n : ℕ
F : TypeVec.{u} (n + 1) → Type u
mvf : MvFunctor F
q : MvQPF F
α : TypeVec.{u} n
r : Cofix F α → Cofix F α → Prop
h' : ∀ (x : Cofix F α), r x x
h : ∀ (x y : Cofix F α), r x y → (TypeVec.id ::: Quot.mk r) <$$> dest x = (TypeVec.id ::: Quot.mk r) <$$> dest y
x y : M (P F) α
rxy : r (Quot.mk Mcongr x) (Quot.mk Mcongr y)
r' : M (P F) α → M (P F) α → Prop := fun x y => r (Quot.mk Mcongr x) (Quot.mk Mcongr y)
hr' : r' = fun x y => r (Quot.mk Mcongr x) (Quot.mk Mcongr y)
a b : M (P F) α
r'ab : r' a b
h₀ :
  (TypeVec.id ::: Quot.mk r ∘ Quot.mk Mcongr) <$$> MvQPF.abs (M.dest (P F) a) =
    (TypeVec.id ::: Quot.mk r ∘ Quot.mk Mcongr) <$$> MvQPF.abs (M.dest (P F) b)
h₁ : ∀ (u v : M (P F) α), Mcongr u v → Quot.mk r' u = Quot.mk r' v
c : Cofix F α
⊢ ∀ (a : M (P F) α) (b : Cofix F α),
    r (Quot.mk Mcongr a) b → Quot.lift (Quot.mk r') h₁ (Quot.mk Mcongr a) = Quot.lift (Quot.mk r') h₁ b

Next tactic:
clear c
private theorem Cofix.bisim_aux {α : TypeVec n} (r : Cofix F α → Cofix F α → Prop) (h' : ∀ x, r x x)
    (h : ∀ x y, r x y →
      appendFun id (Quot.mk r) <$$> Cofix.dest x = appendFun id (Quot.mk r) <$$> Cofix.dest y) :
    ∀ x y, r x y → x = y := by
  intro x
  rcases x; clear x; rename M (P F) α => x;
  intro y
  rcases y; clear y; rename M (P F) α => y;
  intro rxy
  apply Quot.sound
  let r' := fun x y => r (Quot.mk _ x) (Quot.mk _ y)
  have hr' : r' = fun x y => r (Quot.mk _ x) (Quot.mk _ y) := rfl
  have : IsPrecongr r' := by
    intro a b r'ab
    have h₀ :
      appendFun id (Quot.mk r ∘ Quot.mk Mcongr) <$$> MvQPF.abs (M.dest q.P a) =
        appendFun id (Quot.mk r ∘ Quot.mk Mcongr) <$$> MvQPF.abs (M.dest q.P b) :=
      by rw [appendFun_comp_id, comp_map, comp_map]; exact h _ _ r'ab
    have h₁ : ∀ u v : q.P.M α, Mcongr u v → Quot.mk r' u = Quot.mk r' v := by
      intro u v cuv
      apply Quot.sound
      dsimp [hr']
      rw [Quot.sound cuv]
      apply h'
    let f : Quot r → Quot r' :=
      Quot.lift (Quot.lift (Quot.mk r') h₁)
        (by
          intro c
          apply Quot.inductionOn
            (motive := fun c =>
              ∀b, r c b → Quot.lift (Quot.mk r') h₁ c = Quot.lift (Quot.mk r') h₁ b) c
          clear c
          

Proof state:
n : ℕ
F : TypeVec.{u} (n + 1) → Type u
mvf : MvFunctor F
q : MvQPF F
α : TypeVec.{u} n
r : Cofix F α → Cofix F α → Prop
h' : ∀ (x : Cofix F α), r x x
h : ∀ (x y : Cofix F α), r x y → (TypeVec.id ::: Quot.mk r) <$$> dest x = (TypeVec.id ::: Quot.mk r) <$$> dest y
x y : M (P F) α
rxy : r (Quot.mk Mcongr x) (Quot.mk Mcongr y)
r' : M (P F) α → M (P F) α → Prop := fun x y => r (Quot.mk Mcongr x) (Quot.mk Mcongr y)
hr' : r' = fun x y => r (Quot.mk Mcongr x) (Quot.mk Mcongr y)
a b : M (P F) α
r'ab : r' a b
h₀ :
  (TypeVec.id ::: Quot.mk r ∘ Quot.mk Mcongr) <$$> MvQPF.abs (M.dest (P F) a) =
    (TypeVec.id ::: Quot.mk r ∘ Quot.mk Mcongr) <$$> MvQPF.abs (M.dest (P F) b)
h₁ : ∀ (u v : M (P F) α), Mcongr u v → Quot.mk r' u = Quot.mk r' v
⊢ ∀ (a : M (P F) α) (b : Cofix F α),
    r (Quot.mk Mcongr a) b → Quot.lift (Quot.mk r') h₁ (Quot.mk Mcongr a) = Quot.lift (Quot.mk r') h₁ b

Next tactic:
intro c d
private theorem Cofix.bisim_aux {α : TypeVec n} (r : Cofix F α → Cofix F α → Prop) (h' : ∀ x, r x x)
    (h : ∀ x y, r x y →
      appendFun id (Quot.mk r) <$$> Cofix.dest x = appendFun id (Quot.mk r) <$$> Cofix.dest y) :
    ∀ x y, r x y → x = y := by
  intro x
  rcases x; clear x; rename M (P F) α => x;
  intro y
  rcases y; clear y; rename M (P F) α => y;
  intro rxy
  apply Quot.sound
  let r' := fun x y => r (Quot.mk _ x) (Quot.mk _ y)
  have hr' : r' = fun x y => r (Quot.mk _ x) (Quot.mk _ y) := rfl
  have : IsPrecongr r' := by
    intro a b r'ab
    have h₀ :
      appendFun id (Quot.mk r ∘ Quot.mk Mcongr) <$$> MvQPF.abs (M.dest q.P a) =
        appendFun id (Quot.mk r ∘ Quot.mk Mcongr) <$$> MvQPF.abs (M.dest q.P b) :=
      by rw [appendFun_comp_id, comp_map, comp_map]; exact h _ _ r'ab
    have h₁ : ∀ u v : q.P.M α, Mcongr u v → Quot.mk r' u = Quot.mk r' v := by
      intro u v cuv
      apply Quot.sound
      dsimp [hr']
      rw [Quot.sound cuv]
      apply h'
    let f : Quot r → Quot r' :=
      Quot.lift (Quot.lift (Quot.mk r') h₁)
        (by
          intro c
          apply Quot.inductionOn
            (motive := fun c =>
              ∀b, r c b → Quot.lift (Quot.mk r') h₁ c = Quot.lift (Quot.mk r') h₁ b) c
          clear c
          intro c d
          

Proof state:
n : ℕ
F : TypeVec.{u} (n + 1) → Type u
mvf : MvFunctor F
q : MvQPF F
α : TypeVec.{u} n
r : Cofix F α → Cofix F α → Prop
h' : ∀ (x : Cofix F α), r x x
h : ∀ (x y : Cofix F α), r x y → (TypeVec.id ::: Quot.mk r) <$$> dest x = (TypeVec.id ::: Quot.mk r) <$$> dest y
x y : M (P F) α
rxy : r (Quot.mk Mcongr x) (Quot.mk Mcongr y)
r' : M (P F) α → M (P F) α → Prop := fun x y => r (Quot.mk Mcongr x) (Quot.mk Mcongr y)
hr' : r' = fun x y => r (Quot.mk Mcongr x) (Quot.mk Mcongr y)
a b : M (P F) α
r'ab : r' a b
h₀ :
  (TypeVec.id ::: Quot.mk r ∘ Quot.mk Mcongr) <$$> MvQPF.abs (M.dest (P F) a) =
    (TypeVec.id ::: Quot.mk r ∘ Quot.mk Mcongr) <$$> MvQPF.abs (M.dest (P F) b)
h₁ : ∀ (u v : M (P F) α), Mcongr u v → Quot.mk r' u = Quot.mk r' v
c : M (P F) α
d : Cofix F α
⊢ r (Quot.mk Mcongr c) d → Quot.lift (Quot.mk r') h₁ (Quot.mk Mcongr c) = Quot.lift (Quot.mk r') h₁ d

Next tactic:
apply Quot.inductionOn
            (motive := fun d => r (Quot.mk Mcongr c) d →
              Quot.lift (Quot.mk r') h₁ (Quot.mk Mcongr c) = Quot.lift (Quot.mk r') h₁ d) d
private theorem Cofix.bisim_aux {α : TypeVec n} (r : Cofix F α → Cofix F α → Prop) (h' : ∀ x, r x x)
    (h : ∀ x y, r x y →
      appendFun id (Quot.mk r) <$$> Cofix.dest x = appendFun id (Quot.mk r) <$$> Cofix.dest y) :
    ∀ x y, r x y → x = y := by
  intro x
  rcases x; clear x; rename M (P F) α => x;
  intro y
  rcases y; clear y; rename M (P F) α => y;
  intro rxy
  apply Quot.sound
  let r' := fun x y => r (Quot.mk _ x) (Quot.mk _ y)
  have hr' : r' = fun x y => r (Quot.mk _ x) (Quot.mk _ y) := rfl
  have : IsPrecongr r' := by
    intro a b r'ab
    have h₀ :
      appendFun id (Quot.mk r ∘ Quot.mk Mcongr) <$$> MvQPF.abs (M.dest q.P a) =
        appendFun id (Quot.mk r ∘ Quot.mk Mcongr) <$$> MvQPF.abs (M.dest q.P b) :=
      by rw [appendFun_comp_id, comp_map, comp_map]; exact h _ _ r'ab
    have h₁ : ∀ u v : q.P.M α, Mcongr u v → Quot.mk r' u = Quot.mk r' v := by
      intro u v cuv
      apply Quot.sound
      dsimp [hr']
      rw [Quot.sound cuv]
      apply h'
    let f : Quot r → Quot r' :=
      Quot.lift (Quot.lift (Quot.mk r') h₁)
        (by
          intro c
          apply Quot.inductionOn
            (motive := fun c =>
              ∀b, r c b → Quot.lift (Quot.mk r') h₁ c = Quot.lift (Quot.mk r') h₁ b) c
          clear c
          intro c d
          apply Quot.inductionOn
            (motive := fun d => r (Quot.mk Mcongr c) d →
              Quot.lift (Quot.mk r') h₁ (Quot.mk Mcongr c) = Quot.lift (Quot.mk r') h₁ d) d
          

Proof state:
n : ℕ
F : TypeVec.{u} (n + 1) → Type u
mvf : MvFunctor F
q : MvQPF F
α : TypeVec.{u} n
r : Cofix F α → Cofix F α → Prop
h' : ∀ (x : Cofix F α), r x x
h : ∀ (x y : Cofix F α), r x y → (TypeVec.id ::: Quot.mk r) <$$> dest x = (TypeVec.id ::: Quot.mk r) <$$> dest y
x y : M (P F) α
rxy : r (Quot.mk Mcongr x) (Quot.mk Mcongr y)
r' : M (P F) α → M (P F) α → Prop := fun x y => r (Quot.mk Mcongr x) (Quot.mk Mcongr y)
hr' : r' = fun x y => r (Quot.mk Mcongr x) (Quot.mk Mcongr y)
a b : M (P F) α
r'ab : r' a b
h₀ :
  (TypeVec.id ::: Quot.mk r ∘ Quot.mk Mcongr) <$$> MvQPF.abs (M.dest (P F) a) =
    (TypeVec.id ::: Quot.mk r ∘ Quot.mk Mcongr) <$$> MvQPF.abs (M.dest (P F) b)
h₁ : ∀ (u v : M (P F) α), Mcongr u v → Quot.mk r' u = Quot.mk r' v
c : M (P F) α
d : Cofix F α
⊢ ∀ (a : M (P F) α),
    r (Quot.mk Mcongr c) (Quot.mk Mcongr a) →
      Quot.lift (Quot.mk r') h₁ (Quot.mk Mcongr c) = Quot.lift (Quot.mk r') h₁ (Quot.mk Mcongr a)

Next tactic:
clear d
private theorem Cofix.bisim_aux {α : TypeVec n} (r : Cofix F α → Cofix F α → Prop) (h' : ∀ x, r x x)
    (h : ∀ x y, r x y →
      appendFun id (Quot.mk r) <$$> Cofix.dest x = appendFun id (Quot.mk r) <$$> Cofix.dest y) :
    ∀ x y, r x y → x = y := by
  intro x
  rcases x; clear x; rename M (P F) α => x;
  intro y
  rcases y; clear y; rename M (P F) α => y;
  intro rxy
  apply Quot.sound
  let r' := fun x y => r (Quot.mk _ x) (Quot.mk _ y)
  have hr' : r' = fun x y => r (Quot.mk _ x) (Quot.mk _ y) := rfl
  have : IsPrecongr r' := by
    intro a b r'ab
    have h₀ :
      appendFun id (Quot.mk r ∘ Quot.mk Mcongr) <$$> MvQPF.abs (M.dest q.P a) =
        appendFun id (Quot.mk r ∘ Quot.mk Mcongr) <$$> MvQPF.abs (M.dest q.P b) :=
      by rw [appendFun_comp_id, comp_map, comp_map]; exact h _ _ r'ab
    have h₁ : ∀ u v : q.P.M α, Mcongr u v → Quot.mk r' u = Quot.mk r' v := by
      intro u v cuv
      apply Quot.sound
      dsimp [hr']
      rw [Quot.sound cuv]
      apply h'
    let f : Quot r → Quot r' :=
      Quot.lift (Quot.lift (Quot.mk r') h₁)
        (by
          intro c
          apply Quot.inductionOn
            (motive := fun c =>
              ∀b, r c b → Quot.lift (Quot.mk r') h₁ c = Quot.lift (Quot.mk r') h₁ b) c
          clear c
          intro c d
          apply Quot.inductionOn
            (motive := fun d => r (Quot.mk Mcongr c) d →
              Quot.lift (Quot.mk r') h₁ (Quot.mk Mcongr c) = Quot.lift (Quot.mk r') h₁ d) d
          clear d
          

Proof state:
n : ℕ
F : TypeVec.{u} (n + 1) → Type u
mvf : MvFunctor F
q : MvQPF F
α : TypeVec.{u} n
r : Cofix F α → Cofix F α → Prop
h' : ∀ (x : Cofix F α), r x x
h : ∀ (x y : Cofix F α), r x y → (TypeVec.id ::: Quot.mk r) <$$> dest x = (TypeVec.id ::: Quot.mk r) <$$> dest y
x y : M (P F) α
rxy : r (Quot.mk Mcongr x) (Quot.mk Mcongr y)
r' : M (P F) α → M (P F) α → Prop := fun x y => r (Quot.mk Mcongr x) (Quot.mk Mcongr y)
hr' : r' = fun x y => r (Quot.mk Mcongr x) (Quot.mk Mcongr y)
a b : M (P F) α
r'ab : r' a b
h₀ :
  (TypeVec.id ::: Quot.mk r ∘ Quot.mk Mcongr) <$$> MvQPF.abs (M.dest (P F) a) =
    (TypeVec.id ::: Quot.mk r ∘ Quot.mk Mcongr) <$$> MvQPF.abs (M.dest (P F) b)
h₁ : ∀ (u v : M (P F) α), Mcongr u v → Quot.mk r' u = Quot.mk r' v
c : M (P F) α
⊢ ∀ (a : M (P F) α),
    r (Quot.mk Mcongr c) (Quot.mk Mcongr a) →
      Quot.lift (Quot.mk r') h₁ (Quot.mk Mcongr c) = Quot.lift (Quot.mk r') h₁ (Quot.mk Mcongr a)

Next tactic:
intro d rcd
private theorem Cofix.bisim_aux {α : TypeVec n} (r : Cofix F α → Cofix F α → Prop) (h' : ∀ x, r x x)
    (h : ∀ x y, r x y →
      appendFun id (Quot.mk r) <$$> Cofix.dest x = appendFun id (Quot.mk r) <$$> Cofix.dest y) :
    ∀ x y, r x y → x = y := by
  intro x
  rcases x; clear x; rename M (P F) α => x;
  intro y
  rcases y; clear y; rename M (P F) α => y;
  intro rxy
  apply Quot.sound
  let r' := fun x y => r (Quot.mk _ x) (Quot.mk _ y)
  have hr' : r' = fun x y => r (Quot.mk _ x) (Quot.mk _ y) := rfl
  have : IsPrecongr r' := by
    intro a b r'ab
    have h₀ :
      appendFun id (Quot.mk r ∘ Quot.mk Mcongr) <$$> MvQPF.abs (M.dest q.P a) =
        appendFun id (Quot.mk r ∘ Quot.mk Mcongr) <$$> MvQPF.abs (M.dest q.P b) :=
      by rw [appendFun_comp_id, comp_map, comp_map]; exact h _ _ r'ab
    have h₁ : ∀ u v : q.P.M α, Mcongr u v → Quot.mk r' u = Quot.mk r' v := by
      intro u v cuv
      apply Quot.sound
      dsimp [hr']
      rw [Quot.sound cuv]
      apply h'
    let f : Quot r → Quot r' :=
      Quot.lift (Quot.lift (Quot.mk r') h₁)
        (by
          intro c
          apply Quot.inductionOn
            (motive := fun c =>
              ∀b, r c b → Quot.lift (Quot.mk r') h₁ c = Quot.lift (Quot.mk r') h₁ b) c
          clear c
          intro c d
          apply Quot.inductionOn
            (motive := fun d => r (Quot.mk Mcongr c) d →
              Quot.lift (Quot.mk r') h₁ (Quot.mk Mcongr c) = Quot.lift (Quot.mk r') h₁ d) d
          clear d
          intro d rcd; 

Proof state:
n : ℕ
F : TypeVec.{u} (n + 1) → Type u
mvf : MvFunctor F
q : MvQPF F
α : TypeVec.{u} n
r : Cofix F α → Cofix F α → Prop
h' : ∀ (x : Cofix F α), r x x
h : ∀ (x y : Cofix F α), r x y → (TypeVec.id ::: Quot.mk r) <$$> dest x = (TypeVec.id ::: Quot.mk r) <$$> dest y
x y : M (P F) α
rxy : r (Quot.mk Mcongr x) (Quot.mk Mcongr y)
r' : M (P F) α → M (P F) α → Prop := fun x y => r (Quot.mk Mcongr x) (Quot.mk Mcongr y)
hr' : r' = fun x y => r (Quot.mk Mcongr x) (Quot.mk Mcongr y)
a b : M (P F) α
r'ab : r' a b
h₀ :
  (TypeVec.id ::: Quot.mk r ∘ Quot.mk Mcongr) <$$> MvQPF.abs (M.dest (P F) a) =
    (TypeVec.id ::: Quot.mk r ∘ Quot.mk Mcongr) <$$> MvQPF.abs (M.dest (P F) b)
h₁ : ∀ (u v : M (P F) α), Mcongr u v → Quot.mk r' u = Quot.mk r' v
c d : M (P F) α
rcd : r (Quot.mk Mcongr c) (Quot.mk Mcongr d)
⊢ Quot.lift (Quot.mk r') h₁ (Quot.mk Mcongr c) = Quot.lift (Quot.mk r') h₁ (Quot.mk Mcongr d)

Next tactic:
apply Quot.sound
private theorem Cofix.bisim_aux {α : TypeVec n} (r : Cofix F α → Cofix F α → Prop) (h' : ∀ x, r x x)
    (h : ∀ x y, r x y →
      appendFun id (Quot.mk r) <$$> Cofix.dest x = appendFun id (Quot.mk r) <$$> Cofix.dest y) :
    ∀ x y, r x y → x = y := by
  intro x
  rcases x; clear x; rename M (P F) α => x;
  intro y
  rcases y; clear y; rename M (P F) α => y;
  intro rxy
  apply Quot.sound
  let r' := fun x y => r (Quot.mk _ x) (Quot.mk _ y)
  have hr' : r' = fun x y => r (Quot.mk _ x) (Quot.mk _ y) := rfl
  have : IsPrecongr r' := by
    intro a b r'ab
    have h₀ :
      appendFun id (Quot.mk r ∘ Quot.mk Mcongr) <$$> MvQPF.abs (M.dest q.P a) =
        appendFun id (Quot.mk r ∘ Quot.mk Mcongr) <$$> MvQPF.abs (M.dest q.P b) :=
      by rw [appendFun_comp_id, comp_map, comp_map]; exact h _ _ r'ab
    have h₁ : ∀ u v : q.P.M α, Mcongr u v → Quot.mk r' u = Quot.mk r' v := by
      intro u v cuv
      apply Quot.sound
      dsimp [hr']
      rw [Quot.sound cuv]
      apply h'
    let f : Quot r → Quot r' :=
      Quot.lift (Quot.lift (Quot.mk r') h₁)
        (by
          intro c
          apply Quot.inductionOn
            (motive := fun c =>
              ∀b, r c b → Quot.lift (Quot.mk r') h₁ c = Quot.lift (Quot.mk r') h₁ b) c
          clear c
          intro c d
          apply Quot.inductionOn
            (motive := fun d => r (Quot.mk Mcongr c) d →
              Quot.lift (Quot.mk r') h₁ (Quot.mk Mcongr c) = Quot.lift (Quot.mk r') h₁ d) d
          clear d
          intro d rcd; apply Quot.sound; 

Proof state:
case a
n : ℕ
F : TypeVec.{u} (n + 1) → Type u
mvf : MvFunctor F
q : MvQPF F
α : TypeVec.{u} n
r : Cofix F α → Cofix F α → Prop
h' : ∀ (x : Cofix F α), r x x
h : ∀ (x y : Cofix F α), r x y → (TypeVec.id ::: Quot.mk r) <$$> dest x = (TypeVec.id ::: Quot.mk r) <$$> dest y
x y : M (P F) α
rxy : r (Quot.mk Mcongr x) (Quot.mk Mcongr y)
r' : M (P F) α → M (P F) α → Prop := fun x y => r (Quot.mk Mcongr x) (Quot.mk Mcongr y)
hr' : r' = fun x y => r (Quot.mk Mcongr x) (Quot.mk Mcongr y)
a b : M (P F) α
r'ab : r' a b
h₀ :
  (TypeVec.id ::: Quot.mk r ∘ Quot.mk Mcongr) <$$> MvQPF.abs (M.dest (P F) a) =
    (TypeVec.id ::: Quot.mk r ∘ Quot.mk Mcongr) <$$> MvQPF.abs (M.dest (P F) b)
h₁ : ∀ (u v : M (P F) α), Mcongr u v → Quot.mk r' u = Quot.mk r' v
c d : M (P F) α
rcd : r (Quot.mk Mcongr c) (Quot.mk Mcongr d)
⊢ r' c d

Next tactic:
apply rcd