mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.GroupTheory.Perm.List

Goal state before:
pp: α : Type u_1
inst✝ : DecidableEq α
x : α
xs : List α
⊢ (x :: xs).formPerm ((x :: xs).getLast ⋯) = x

Tactic:
induction xs using List.reverseRecOn generalizing x

Goal state after:
case nil
α : Type u_1
inst✝ : DecidableEq α
x : α
⊢ [x].formPerm ([x].getLast ⋯) = x

case append_singleton
α : Type u_1
inst✝ : DecidableEq α
l✝ : List α
a✝¹ : α
a✝ : ∀ (x : α), (x :: l✝).formPerm ((x :: l✝).getLast ⋯) = x
x : α
⊢ (x :: (l✝ ++ [a✝¹])).formPerm ((x :: (l✝ ++ [a✝¹])).getLast ⋯) = x
Module: Mathlib.GroupTheory.Perm.List

Goal state before:
pp: case zero
α : Type u_1
inst✝ : DecidableEq α
xs : List α
h : xs.Nodup
hn : 0 + 1 < xs.length
⊢ xs.formPerm xs[0] = xs[0 + 1]

Tactic:
simpa using formPerm_apply_getElem_zero _ h _

Goal state after:
Module: Mathlib.GroupTheory.Perm.Support

Goal state before:
pp: case cons
α : Type u_1
inst✝¹ : DecidableEq α
inst✝ : Fintype α
f hd : Perm α
tl : List (Perm α)
IH : f ∈ tl → List.Pairwise Disjoint tl → ∀ x ∈ f.support, f x = tl.prod x
h : f ∈ hd :: tl
hl : List.Pairwise Disjoint (hd :: tl)
x : α
hx : x ∈ f.support
⊢ f x = (hd :: tl).prod x

Tactic:
List.pairwise_cons

Goal state after:
case cons
α : Type u_1
inst✝¹ : DecidableEq α
inst✝ : Fintype α
f hd : Perm α
tl : List (Perm α)
IH : f ∈ tl → List.Pairwise Disjoint tl → ∀ x ∈ f.support, f x = tl.prod x
h : f ∈ hd :: tl
hl : (∀ a' ∈ tl, hd.Disjoint a') ∧ List.Pairwise Disjoint tl
x : α
hx : x ∈ f.support
⊢ f x = (hd :: tl).prod x
Module: Mathlib.GroupTheory.Perm.List

Goal state before:
pp: α : Type u_1
inst✝ : DecidableEq α
x y x' y' : α
l l' : List α
hd : (x :: y :: l).Nodup
hd' : (x' :: y' :: l').Nodup
h : ∀ (x_1 : α), (x :: y :: l).formPerm x_1 = (x' :: y' :: l').formPerm x_1
hx : x' ∈ x :: y :: l
n : ℕ
hn : n < (x :: y :: l).length
hx' : (x :: y :: l).get ⟨n, hn⟩ = x'
⊢ (x :: y :: l).toFinset.card = (x' :: y' :: l').dedup.length

Tactic:
← card_toFinset

Goal state after:
α : Type u_1
inst✝ : DecidableEq α
x y x' y' : α
l l' : List α
hd : (x :: y :: l).Nodup
hd' : (x' :: y' :: l').Nodup
h : ∀ (x_1 : α), (x :: y :: l).formPerm x_1 = (x' :: y' :: l').formPerm x_1
hx : x' ∈ x :: y :: l
n : ℕ
hn : n < (x :: y :: l).length
hx' : (x :: y :: l).get ⟨n, hn⟩ = x'
⊢ (x :: y :: l).toFinset.card = (x' :: y' :: l').toFinset.card
Module: Mathlib.Data.Fintype.Perm

Goal state before:
pp: case refine_3
α : Type u_1
inst✝ : DecidableEq α
a : α
l : List α
hl : (a :: l).Nodup
hl' : l.Nodup
hln' : (permsOfList l).Nodup
hmeml : ∀ {f : Equiv.Perm α}, f ∈ permsOfList l → f a = a
i j : ℕ
hi : i < l.length
hj : j < l.length
hij : i < j
x : Equiv.Perm α
hx₁ : x ∈ (fun b ↦ List.map (fun f ↦ Equiv.swap a b * f) (permsOfList l)) l[i]
hx₂ : x ∈ (fun b ↦ List.map (fun f ↦ Equiv.swap a b * f) (permsOfList l)) l[j]
f : Equiv.Perm α
hf : f ∈ permsOfList l ∧ Equiv.swap a l[i] * f = x
g : Equiv.Perm α
hg : g ∈ permsOfList l ∧ Equiv.swap a l[j] * g = x
hix : x a = l[i]
⊢ False

Tactic:
have hiy : x a = l[j] := by
        rw [← hg.2, mul_apply, hmeml hg.1, swap_apply_left]

Goal state after:
case refine_3
α : Type u_1
inst✝ : DecidableEq α
a : α
l : List α
hl : (a :: l).Nodup
hl' : l.Nodup
hln' : (permsOfList l).Nodup
hmeml : ∀ {f : Equiv.Perm α}, f ∈ permsOfList l → f a = a
i j : ℕ
hi : i < l.length
hj : j < l.length
hij : i < j
x : Equiv.Perm α
hx₁ : x ∈ (fun b ↦ List.map (fun f ↦ Equiv.swap a b * f) (permsOfList l)) l[i]
hx₂ : x ∈ (fun b ↦ List.map (fun f ↦ Equiv.swap a b * f) (permsOfList l)) l[j]
f : Equiv.Perm α
hf : f ∈ permsOfList l ∧ Equiv.swap a l[i] * f = x
g : Equiv.Perm α
hg : g ∈ permsOfList l ∧ Equiv.swap a l[j] * g = x
hix : x a = l[i]
hiy : x a = l[j]
⊢ False
Module: Mathlib.GroupTheory.Perm.List

Goal state before:
pp: α : Type u_1
inst✝ : DecidableEq α
l : List α
hl : l.Nodup
x : α
hx : x ∈ l
⊢ l.formPerm x = x ↔ l.length ≤ 1

Tactic:
obtain ⟨k, hk, rfl⟩ := getElem_of_mem hx
  rw [formPerm_apply_getElem _ hl k hk, hl.getElem_inj_iff]
  cases hn : l.length
  · exact absurd k.zero_le (hk.trans_le hn.le).not_ge
  · rw [hn] at hk
    rcases (Nat.le_of_lt_succ hk).eq_or_lt with hk' | hk'
    · simp [← hk', eq_comm]
    · simpa [Nat.mod_eq_of_lt (Nat.succ_lt_succ hk'), Nat.succ_lt_succ_iff] using
        (k.zero_le.trans_lt hk').ne.symm

Goal state after:
Module: Mathlib.GroupTheory.Perm.Cycle.Basic

Goal state before:
pp: α : Type u_2
f : Perm α
inst✝¹ : DecidableEq α
inst✝ : Fintype α
n : ℕ
h2 : f.support ⊆ (f ^ n).support
key : ∀ (x : α), (f ^ n) x ≠ x ↔ f x ≠ x
x : α
hx1 : (f ^ n) x ≠ x
hx2 : ∀ ⦃y : α⦄, (f ^ n) y ≠ y → (f ^ n).SameCycle x y
y : α
hy : f y ≠ y
i : ℤ
h✝ : ((f ^ n) ^ i) x = y
⊢ (f ^ (↑n * i)) x = y

Tactic:
by rwa [zpow_mul]

Goal state after:
Module: Mathlib.GroupTheory.Perm.Cycle.Basic

Goal state before:
pp: case intro.mp
β : Type u_3
inst✝ : Finite β
f : Perm β
hf : f.IsCycle
n : ℕ
val✝ : Fintype β
h : (f ^ n).IsCycle
hr : (f ^ n).support = f.support
this : orderOf f / (orderOf f).gcd n = orderOf f
⊢ n.Coprime (orderOf f)

Tactic:
Nat.div_eq_self

Goal state after:
case intro.mp
β : Type u_3
inst✝ : Finite β
f : Perm β
hf : f.IsCycle
n : ℕ
val✝ : Fintype β
h : (f ^ n).IsCycle
hr : (f ^ n).support = f.support
this : orderOf f = 0 ∨ (orderOf f).gcd n = 1
⊢ n.Coprime (orderOf f)
Module: Mathlib.GroupTheory.Perm.Sign

Goal state before:
pp: α : Type u
inst✝³ : DecidableEq α
β : Type v
inst✝² : Fintype α
inst✝¹ : DecidableEq β
inst✝ : Fintype β
σ : α → Perm β
l : List α
hl : l.Nodup
mem_l : ∀ (x : α), x ∈ l
l_to_finset : l.toFinset = univ
⊢ sign (prodCongrRight σ) = ∏ k, sign (σ k)

Tactic:
rw [← prod_prodExtendRight σ hl mem_l, map_list_prod sign, List.map_map, ← l_to_finset,
    List.prod_toFinset _ hl]

Goal state after:
α : Type u
inst✝³ : DecidableEq α
β : Type v
inst✝² : Fintype α
inst✝¹ : DecidableEq β
inst✝ : Fintype β
σ : α → Perm β
l : List α
hl : l.Nodup
mem_l : ∀ (x : α), x ∈ l
l_to_finset : l.toFinset = univ
⊢ (List.map (⇑sign ∘ fun a ↦ prodExtendRight a (σ a)) l).prod = (List.map (fun k ↦ sign (σ k)) l).prod
Module: Mathlib.GroupTheory.NoncommPiCoprod

Goal state before:
pp: G : Type u_1
inst✝² : Group G
ι : Type u_2
H : ι → Type u_3
inst✝¹ : (i : ι) → Group (H i)
ϕ : (i : ι) → H i →* G
inst✝ : Fintype ι
hcomm : Pairwise fun i j ↦ ∀ (x : H i) (y : H j), Commute ((ϕ i) x) ((ϕ j) y)
hind : iSupIndep fun i ↦ (ϕ i).range
hinj : ∀ (i : ι), Function.Injective ⇑(ϕ i)
f : (i : ι) → H i
heq1 : f ∈ (noncommPiCoprod ϕ hcomm).ker
this : ∀ i ∈ Finset.univ, (ϕ i) (f i) = 1
⊢ f ∈ ⊥

Tactic:
ext i

Goal state after:
G : Type u_1
inst✝² : Group G
ι : Type u_2
H : ι → Type u_3
inst✝¹ : (i : ι) → Group (H i)
ϕ : (i : ι) → H i →* G
inst✝ : Fintype ι
hcomm : Pairwise fun i j ↦ ∀ (x : H i) (y : H j), Commute ((ϕ i) x) ((ϕ j) y)
hind : iSupIndep fun i ↦ (ϕ i).range
hinj : ∀ (i : ι), Function.Injective ⇑(ϕ i)
f : (i : ι) → H i
heq1 : f ∈ (noncommPiCoprod ϕ hcomm).ker
this : ∀ i ∈ Finset.univ, (ϕ i) (f i) = 1
i : ι
⊢ f i = 1 i
Module: Mathlib.GroupTheory.Perm.Cycle.Basic

Goal state before:
pp: case mp
α : Type u_2
inst✝¹ : Fintype α
inst✝ : DecidableEq α
g c : Perm α
hc : c.IsCycle
⊢ Commute g c →
    ∃ (hc' : ∀ (x : α), g x ∈ c.support ↔ x ∈ c.support), g.subtypePerm hc' ∈ Subgroup.zpowers c.subtypePermOfSupport

pp: case mpr
α : Type u_2
inst✝¹ : Fintype α
inst✝ : DecidableEq α
g c : Perm α
hc : c.IsCycle
⊢ (∃ (hc' : ∀ (x : α), g x ∈ c.support ↔ x ∈ c.support), g.subtypePerm hc' ∈ Subgroup.zpowers c.subtypePermOfSupport) →
    Commute g c

Tactic:
· intro hgc
    have hgc' := mem_support_iff_of_commute hgc
    use hgc'
    obtain ⟨a, ha⟩ := IsCycle.nonempty_support hc
    obtain ⟨i, hi⟩ := hc.sameCycle (mem_support.mp ha) (mem_support.mp ((hgc' a).mpr ha))
    use i
    ext ⟨x, hx⟩
    simp only [subtypePermOfSupport, Subtype.coe_mk, subtypePerm_apply]
    rw [subtypePerm_apply_zpow_of_mem]
    obtain ⟨j, rfl⟩ := hc.sameCycle (mem_support.mp ha) (mem_support.mp hx)
    simp only [← mul_apply, Commute.eq (Commute.zpow_right hgc j)]
    rw [← zpow_add, add_comm i j, zpow_add]
    simp only [mul_apply, EmbeddingLike.apply_eq_iff_eq]
    exact hi

Goal state after:
case mpr
α : Type u_2
inst✝¹ : Fintype α
inst✝ : DecidableEq α
g c : Perm α
hc : c.IsCycle
⊢ (∃ (hc' : ∀ (x : α), g x ∈ c.support ↔ x ∈ c.support), g.subtypePerm hc' ∈ Subgroup.zpowers c.subtypePermOfSupport) →
    Commute g c
Module: Mathlib.GroupTheory.Perm.Fin

Goal state before:
pp: n : ℕ
⊢ finRotate n.succ = decomposeFin.symm (1, finRotate n)

Tactic:
ext i

Goal state after:
n : ℕ
i : Fin n.succ
⊢ ↑((finRotate n.succ) i) = ↑((decomposeFin.symm (1, finRotate n)) i)
Module: Mathlib.GroupTheory.Perm.Fin

Goal state before:
pp: n x : ℕ
hx : x < n + 2
⊢ ↑((finRotate (n + 2) ^ ↑⟨x, hx⟩) 0) = ↑⟨x, hx⟩

Tactic:
induction x with

Goal state after:
Module: Mathlib.GroupTheory.Perm.Cycle.Factors

Goal state before:
pp: case neg
ι : Type u_1
α : Type u_2
β : Type u_3
inst✝¹ : DecidableEq α
inst✝ : Fintype α
l✝¹ : List α
f : Perm α
h : ∀ {x : α}, f x ≠ x → x ∈ l✝¹
l✝ : List α
g : Perm α
hfg : ∀ {x : α}, g x ≠ x → f.cycleOf x = g.cycleOf x
x : α
l : List α
hg : ∀ {x_1 : α}, g x_1 ≠ x_1 → x_1 ∈ x :: l
hx : ¬g x = x
y : α
hy : ¬g.SameCycle x y ∧ ¬y = g y
z : α
hz : ¬g.SameCycle x z
⊢ (g * g.cycleOf x) z = (g.cycleOf x * g) z

Tactic:
simp [cycleOf_apply_of_not_sameCycle, hz]

Goal state after:
Module: Mathlib.GroupTheory.Perm.Fin

Goal state before:
pp: n : ℕ
⊢ (last n).cycleRange = finRotate (n + 1)

Tactic:
ext i

Goal state after:
n : ℕ
i : Fin (n + 1)
⊢ ↑((last n).cycleRange i) = ↑((finRotate (n + 1)) i)
Module: Mathlib.GroupTheory.Perm.Cycle.Factors

Goal state before:
pp: ι : Type u_1
α : Type u_2
β : Type u_3
inst✝¹ : DecidableEq α
inst✝ : Fintype α
l✝¹ : List α
f : Perm α
h : ∀ {x : α}, f x ≠ x → x ∈ l✝¹
l✝ : List α
g : Perm α
hfg : ∀ {x : α}, g x ≠ x → f.cycleOf x = g.cycleOf x
x : α
l : List α
hg : ∀ {x_1 : α}, g x_1 ≠ x_1 → x_1 ∈ x :: l
hx : ¬g x = x
m : List (Perm α)
hm₁ : m.prod = (g.cycleOf x)⁻¹ * g
hm₂ : ∀ g' ∈ m, g'.IsCycle
hm₃ : List.Pairwise Disjoint m
⊢ (g.cycleOf x :: m).prod = g ∧ (∀ g' ∈ g.cycleOf x :: m, g'.IsCycle) ∧ List.Pairwise Disjoint (g.cycleOf x :: m)

Tactic:
List.pairwise_cons

Goal state after:
ι : Type u_1
α : Type u_2
β : Type u_3
inst✝¹ : DecidableEq α
inst✝ : Fintype α
l✝¹ : List α
f : Perm α
h : ∀ {x : α}, f x ≠ x → x ∈ l✝¹
l✝ : List α
g : Perm α
hfg : ∀ {x : α}, g x ≠ x → f.cycleOf x = g.cycleOf x
x : α
l : List α
hg : ∀ {x_1 : α}, g x_1 ≠ x_1 → x_1 ∈ x :: l
hx : ¬g x = x
m : List (Perm α)
hm₁ : m.prod = (g.cycleOf x)⁻¹ * g
hm₂ : ∀ g' ∈ m, g'.IsCycle
hm₃ : List.Pairwise Disjoint m
⊢ (g.cycleOf x :: m).prod = g ∧
    (∀ g' ∈ g.cycleOf x :: m, g'.IsCycle) ∧ (∀ a' ∈ m, (g.cycleOf x).Disjoint a') ∧ List.Pairwise Disjoint m
Module: Mathlib.GroupTheory.Perm.Fin

Goal state before:
pp: n : ℕ
α : Type u_1
x : Fin (n + 1) → α
p : Fin (n + 1)
⊢ cons (x p) (p.removeNth x) = x ∘ ⇑(Equiv.symm p.cycleRange)

Tactic:
ext i

Goal state after:
n : ℕ
α : Type u_1
x : Fin (n + 1) → α
p i : Fin (n + 1)
⊢ cons (x p) (p.removeNth x) i = (x ∘ ⇑(Equiv.symm p.cycleRange)) i
Module: Mathlib.GroupTheory.Perm.Fin

Goal state before:
pp: n : ℕ
i j : Fin (n + 1)
hij : i ≤ j
⊢ ⇑(i.cycleIcc j) ∘ j.succAbove = i.succAbove

Tactic:
grind [cycleIcc_of_lt, succAbove_of_castSucc_lt, cycleIcc_of_ge_of_lt,
    succAbove_of_le_castSucc, coeSucc_eq_succ, cycleIcc_of_gt]

Goal state after:
Module: Mathlib.GroupTheory.Perm.Cycle.Factors

Goal state before:
pp: case neg
α : Type u_2
inst✝¹ : DecidableEq α
inst✝ : Fintype α
g c : Perm α
hc : c ∈ g.cycleFactorsFinset
c' : Perm α
hc' : c' ∈ g.cycleFactorsFinset
hcc' : ¬c = c'
⊢ Commute c c'

Tactic:
apply g.cycleFactorsFinset_mem_commute hc hc'

Goal state after:
case neg
α : Type u_2
inst✝¹ : DecidableEq α
inst✝ : Fintype α
g c : Perm α
hc : c ∈ g.cycleFactorsFinset
c' : Perm α
hc' : c' ∈ g.cycleFactorsFinset
hcc' : ¬c = c'
⊢ c ≠ c'
Module: Mathlib.GroupTheory.Perm.Cycle.Type

Goal state before:
pp: case mpr.h₂.hnc.inr
α : Type u_1
inst✝¹ : Fintype α
inst✝ : DecidableEq α
g : Perm α
a : α
hg3 : g.IsThreeCycle
ha : a = g (g a)
⊢ g a = a

Tactic:
suffices (g ^ 3) a = a by simpa [pow_succ, ← ha] using this

Goal state after:
case mpr.h₂.hnc.inr
α : Type u_1
inst✝¹ : Fintype α
inst✝ : DecidableEq α
g : Perm α
a : α
hg3 : g.IsThreeCycle
ha : a = g (g a)
⊢ (g ^ 3) a = a
Module: Mathlib.LinearAlgebra.Multilinear.DFinsupp

Goal state before:
pp: case e_a
ι : Type uι
κ : ι → Type uκ
R : Type uR
ι' : Type u_1
inst✝⁵ : DecidableEq ι
inst✝⁴ : Fintype ι
inst✝³ : CommSemiring R
inst✝² : (i : ι) → Fintype (κ i)
inst✝¹ : (i : ι) → DecidableEq (κ i)
inst✝ : DecidableEq ι'
p : ((i : ι) → κ i) × ι'
r : R
x : (i : ι) → Π₀ (x : κ i), R
⊢ (freeDFinsuppEquiv (DFinsupp.single p 1)) x = DFinsupp.single p.2 (∏ i, (x i) (p.1 i))

Tactic:
ext i

Goal state after:
case e_a
ι : Type uι
κ : ι → Type uκ
R : Type uR
ι' : Type u_1
inst✝⁵ : DecidableEq ι
inst✝⁴ : Fintype ι
inst✝³ : CommSemiring R
inst✝² : (i : ι) → Fintype (κ i)
inst✝¹ : (i : ι) → DecidableEq (κ i)
inst✝ : DecidableEq ι'
p : ((i : ι) → κ i) × ι'
r : R
x : (i : ι) → Π₀ (x : κ i), R
i : ι'
⊢ ((freeDFinsuppEquiv (DFinsupp.single p 1)) x) i = (DFinsupp.single p.2 (∏ i, (x i) (p.1 i))) i
Module: Mathlib.LinearAlgebra.Alternating.Basic

Goal state before:
pp: R : Type u_1
inst✝⁵ : Semiring R
M : Type u_2
inst✝⁴ : AddCommMonoid M
inst✝³ : Module R M
N : Type u_3
inst✝² : AddCommMonoid N
inst✝¹ : Module R N
ι : Type u_7
f : M [⋀^ι]→ₗ[R] N
v : ι → M
inst✝ : DecidableEq ι
i j : ι
hij : i ≠ j
⊢ f (v ∘ ⇑(Equiv.swap i j)) + f v = 0

Tactic:
rw [Equiv.comp_swap_eq_update]

Goal state after:
R : Type u_1
inst✝⁵ : Semiring R
M : Type u_2
inst✝⁴ : AddCommMonoid M
inst✝³ : Module R M
N : Type u_3
inst✝² : AddCommMonoid N
inst✝¹ : Module R N
ι : Type u_7
f : M [⋀^ι]→ₗ[R] N
v : ι → M
inst✝ : DecidableEq ι
i j : ι
hij : i ≠ j
⊢ f (update (update v j (v i)) i (v j)) + f v = 0
Module: Mathlib.Algebra.Category.Ring.Colimits

Goal state before:
pp: J : Type v
inst✝ : SmallCategory J
F : J ⥤ RingCat
s : Cocone F
m : (colimitCocone F).pt ⟶ s.pt
w : ∀ (j : J), (colimitCocone F).ι.app j ≫ m = s.ι.app j
x✝ : ↑(colimitCocone F).pt
x : Prequotient F
⊢ (Hom.hom m) (Quot.mk (⇑(colimitSetoid F)) x) = (Hom.hom (descMorphism F s)) (Quot.mk (⇑(colimitSetoid F)) x)

Tactic:
induction x with

Goal state after:
Module: Mathlib.LinearAlgebra.Multilinear.Basic

Goal state before:
pp: R : Type uR
ι : Type uι
M₁ : ι → Type v₁
M₂ : Type v₂
inst✝⁶ : Semiring R
inst✝⁵ : (i : ι) → AddCommMonoid (M₁ i)
inst✝⁴ : AddCommMonoid M₂
inst✝³ : (i : ι) → Module R (M₁ i)
inst✝² : Module R M₂
f : MultilinearMap R M₁ M₂
α : ι → Type u_1
g : (i : ι) → α i → M₁ i
inst✝¹ : DecidableEq ι
inst✝ : Fintype ι
this : (i : ι) → DecidableEq (α i) := fun i ↦ Classical.decEq (α i)
n : ℕ
IH :
  ∀ m < n,
    ∀ (A : (i : ι) → Finset (α i)),
      ∑ i, #(A i) = m → (f fun i ↦ ∑ j ∈ A i, g i j) = ∑ r ∈ piFinset A, f fun i ↦ g i (r i)
A : (i : ι) → Finset (α i)
h : ∑ i, #(A i) = n
Ai_empty : ∀ (i : ι), (A i).Nonempty
i₀ : ι
hi₀ : 1 < #(A i₀)
j₁ j₂ : α i₀
left✝ : j₁ ∈ A i₀
hj₂ : j₂ ∈ A i₀
right✝ : j₁ ≠ j₂
B : (a : ι) → Finset (α a) := update A i₀ (A i₀ \ {j₂})
C : (a : ι) → Finset (α a) := update A i₀ {j₂}
B_subset_A : ∀ (i : ι), B i ⊆ A i
C_subset_A : ∀ (i : ι), C i ⊆ A i
⊢ (fun i ↦ ∑ j ∈ A i, g i j) = update (fun i ↦ ∑ j ∈ A i, g i j) i₀ (∑ j ∈ B i₀, g i₀ j + ∑ j ∈ C i₀, g i₀ j)

Tactic:
ext i

Goal state after:
R : Type uR
ι : Type uι
M₁ : ι → Type v₁
M₂ : Type v₂
inst✝⁶ : Semiring R
inst✝⁵ : (i : ι) → AddCommMonoid (M₁ i)
inst✝⁴ : AddCommMonoid M₂
inst✝³ : (i : ι) → Module R (M₁ i)
inst✝² : Module R M₂
f : MultilinearMap R M₁ M₂
α : ι → Type u_1
g : (i : ι) → α i → M₁ i
inst✝¹ : DecidableEq ι
inst✝ : Fintype ι
this : (i : ι) → DecidableEq (α i) := fun i ↦ Classical.decEq (α i)
n : ℕ
IH :
  ∀ m < n,
    ∀ (A : (i : ι) → Finset (α i)),
      ∑ i, #(A i) = m → (f fun i ↦ ∑ j ∈ A i, g i j) = ∑ r ∈ piFinset A, f fun i ↦ g i (r i)
A : (i : ι) → Finset (α i)
h : ∑ i, #(A i) = n
Ai_empty : ∀ (i : ι), (A i).Nonempty
i₀ : ι
hi₀ : 1 < #(A i₀)
j₁ j₂ : α i₀
left✝ : j₁ ∈ A i₀
hj₂ : j₂ ∈ A i₀
right✝ : j₁ ≠ j₂
B : (a : ι) → Finset (α a) := update A i₀ (A i₀ \ {j₂})
C : (a : ι) → Finset (α a) := update A i₀ {j₂}
B_subset_A : ∀ (i : ι), B i ⊆ A i
C_subset_A : ∀ (i : ι), C i ⊆ A i
i : ι
⊢ ∑ j ∈ A i, g i j = update (fun i ↦ ∑ j ∈ A i, g i j) i₀ (∑ j ∈ B i₀, g i₀ j + ∑ j ∈ C i₀, g i₀ j) i
Module: Mathlib.Algebra.Category.Ring.Colimits

Goal state before:
pp: J : Type v
inst✝ : SmallCategory J
F : J ⥤ CommRingCat
s : Cocone F
m : (colimitCocone F).pt ⟶ s.pt
w : ∀ (j : J), (colimitCocone F).ι.app j ≫ m = s.ι.app j
x✝ : ↑(colimitCocone F).pt
x : Prequotient F
⊢ (Hom.hom m) (Quot.mk (⇑(colimitSetoid F)) x) = (Hom.hom (descMorphism F s)) (Quot.mk (⇑(colimitSetoid F)) x)

Tactic:
induction x with

Goal state after:
Module: Mathlib.LinearAlgebra.Matrix.Determinant.Basic

Goal state before:
pp: n : Type u_2
inst✝² : DecidableEq n
inst✝¹ : Fintype n
R : Type v
inst✝ : CommRing R
M : Matrix n n R
⊢ Mᵀ.det = M.det

Tactic:
rw [det_apply', det_apply']

Goal state after:
n : Type u_2
inst✝² : DecidableEq n
inst✝¹ : Fintype n
R : Type v
inst✝ : CommRing R
M : Matrix n n R
⊢ ∑ σ, ↑↑(sign σ) * ∏ i, Mᵀ (σ i) i = ∑ σ, ↑↑(sign σ) * ∏ i, M (σ i) i
Module: Mathlib.LinearAlgebra.Multilinear.Basic

Goal state before:
pp: R : Type uR
ι : Type uι
M₁ : ι → Type v₁
M₂ : Type v₂
inst✝⁶ : Semiring R
inst✝⁵ : (i : ι) → AddCommMonoid (M₁ i)
inst✝⁴ : AddCommMonoid M₂
inst✝³ : (i : ι) → Module R (M₁ i)
inst✝² : Module R M₂
f : MultilinearMap R M₁ M₂
α : ι → Type u_1
g : (i : ι) → α i → M₁ i
inst✝¹ : DecidableEq ι
inst✝ : Fintype ι
this : (i : ι) → DecidableEq (α i) := fun i ↦ Classical.decEq (α i)
n : ℕ
IH :
  ∀ m < n,
    ∀ (A : (i : ι) → Finset (α i)),
      ∑ i, #(A i) = m → (f fun i ↦ ∑ j ∈ A i, g i j) = ∑ r ∈ piFinset A, f fun i ↦ g i (r i)
A : (i : ι) → Finset (α i)
h : ∑ i, #(A i) = n
Ai_empty : ∀ (i : ι), (A i).Nonempty
i₀ : ι
hi₀ : 1 < #(A i₀)
j₁ j₂ : α i₀
left✝ : j₁ ∈ A i₀
hj₂ : j₂ ∈ A i₀
right✝ : j₁ ≠ j₂
B : (a : ι) → Finset (α a) := update A i₀ (A i₀ \ {j₂})
C : (a : ι) → Finset (α a) := update A i₀ {j₂}
B_subset_A : ∀ (i : ι), B i ⊆ A i
C_subset_A : ∀ (i : ι), C i ⊆ A i
A_eq_BC : (fun i ↦ ∑ j ∈ A i, g i j) = update (fun i ↦ ∑ j ∈ A i, g i j) i₀ (∑ j ∈ B i₀, g i₀ j + ∑ j ∈ C i₀, g i₀ j)
⊢ update (fun i ↦ ∑ j ∈ A i, g i j) i₀ (∑ j ∈ B i₀, g i₀ j) = fun i ↦ ∑ j ∈ B i, g i j

Tactic:
ext i

Goal state after:
R : Type uR
ι : Type uι
M₁ : ι → Type v₁
M₂ : Type v₂
inst✝⁶ : Semiring R
inst✝⁵ : (i : ι) → AddCommMonoid (M₁ i)
inst✝⁴ : AddCommMonoid M₂
inst✝³ : (i : ι) → Module R (M₁ i)
inst✝² : Module R M₂
f : MultilinearMap R M₁ M₂
α : ι → Type u_1
g : (i : ι) → α i → M₁ i
inst✝¹ : DecidableEq ι
inst✝ : Fintype ι
this : (i : ι) → DecidableEq (α i) := fun i ↦ Classical.decEq (α i)
n : ℕ
IH :
  ∀ m < n,
    ∀ (A : (i : ι) → Finset (α i)),
      ∑ i, #(A i) = m → (f fun i ↦ ∑ j ∈ A i, g i j) = ∑ r ∈ piFinset A, f fun i ↦ g i (r i)
A : (i : ι) → Finset (α i)
h : ∑ i, #(A i) = n
Ai_empty : ∀ (i : ι), (A i).Nonempty
i₀ : ι
hi₀ : 1 < #(A i₀)
j₁ j₂ : α i₀
left✝ : j₁ ∈ A i₀
hj₂ : j₂ ∈ A i₀
right✝ : j₁ ≠ j₂
B : (a : ι) → Finset (α a) := update A i₀ (A i₀ \ {j₂})
C : (a : ι) → Finset (α a) := update A i₀ {j₂}
B_subset_A : ∀ (i : ι), B i ⊆ A i
C_subset_A : ∀ (i : ι), C i ⊆ A i
A_eq_BC : (fun i ↦ ∑ j ∈ A i, g i j) = update (fun i ↦ ∑ j ∈ A i, g i j) i₀ (∑ j ∈ B i₀, g i₀ j + ∑ j ∈ C i₀, g i₀ j)
i : ι
⊢ update (fun i ↦ ∑ j ∈ A i, g i j) i₀ (∑ j ∈ B i₀, g i₀ j) i = ∑ j ∈ B i, g i j
Module: Mathlib.LinearAlgebra.Matrix.Determinant.Basic

Goal state before:
pp: m : Type u_1
n : Type u_2
inst✝⁴ : DecidableEq n
inst✝³ : Fintype n
inst✝² : DecidableEq m
inst✝¹ : Fintype m
R : Type v
inst✝ : CommRing R
e : n ≃ m
A : Matrix m m R
⊢ (A.submatrix ⇑e ⇑e).det = A.det

Tactic:
rw [det_apply', det_apply']

Goal state after:
m : Type u_1
n : Type u_2
inst✝⁴ : DecidableEq n
inst✝³ : Fintype n
inst✝² : DecidableEq m
inst✝¹ : Fintype m
R : Type v
inst✝ : CommRing R
e : n ≃ m
A : Matrix m m R
⊢ ∑ σ, ↑↑(sign σ) * ∏ i, A.submatrix (⇑e) (⇑e) (σ i) i = ∑ σ, ↑↑(sign σ) * ∏ i, A (σ i) i
Module: Mathlib.LinearAlgebra.Multilinear.Basic

Goal state before:
pp: R : Type uR
ι : Type uι
M₁ : ι → Type v₁
M₂ : Type v₂
inst✝⁶ : Semiring R
inst✝⁵ : (i : ι) → AddCommMonoid (M₁ i)
inst✝⁴ : AddCommMonoid M₂
inst✝³ : (i : ι) → Module R (M₁ i)
inst✝² : Module R M₂
f : MultilinearMap R M₁ M₂
α : ι → Type u_1
g : (i : ι) → α i → M₁ i
inst✝¹ : DecidableEq ι
inst✝ : Fintype ι
this : (i : ι) → DecidableEq (α i) := fun i ↦ Classical.decEq (α i)
n : ℕ
IH :
  ∀ m < n,
    ∀ (A : (i : ι) → Finset (α i)),
      ∑ i, #(A i) = m → (f fun i ↦ ∑ j ∈ A i, g i j) = ∑ r ∈ piFinset A, f fun i ↦ g i (r i)
A : (i : ι) → Finset (α i)
h : ∑ i, #(A i) = n
Ai_empty : ∀ (i : ι), (A i).Nonempty
i₀ : ι
hi₀ : 1 < #(A i₀)
j₁ j₂ : α i₀
left✝ : j₁ ∈ A i₀
hj₂ : j₂ ∈ A i₀
right✝ : j₁ ≠ j₂
B : (a : ι) → Finset (α a) := update A i₀ (A i₀ \ {j₂})
C : (a : ι) → Finset (α a) := update A i₀ {j₂}
B_subset_A : ∀ (i : ι), B i ⊆ A i
C_subset_A : ∀ (i : ι), C i ⊆ A i
A_eq_BC : (fun i ↦ ∑ j ∈ A i, g i j) = update (fun i ↦ ∑ j ∈ A i, g i j) i₀ (∑ j ∈ B i₀, g i₀ j + ∑ j ∈ C i₀, g i₀ j)
Beq : update (fun i ↦ ∑ j ∈ A i, g i j) i₀ (∑ j ∈ B i₀, g i₀ j) = fun i ↦ ∑ j ∈ B i, g i j
⊢ update (fun i ↦ ∑ j ∈ A i, g i j) i₀ (∑ j ∈ C i₀, g i₀ j) = fun i ↦ ∑ j ∈ C i, g i j

Tactic:
ext i

Goal state after:
R : Type uR
ι : Type uι
M₁ : ι → Type v₁
M₂ : Type v₂
inst✝⁶ : Semiring R
inst✝⁵ : (i : ι) → AddCommMonoid (M₁ i)
inst✝⁴ : AddCommMonoid M₂
inst✝³ : (i : ι) → Module R (M₁ i)
inst✝² : Module R M₂
f : MultilinearMap R M₁ M₂
α : ι → Type u_1
g : (i : ι) → α i → M₁ i
inst✝¹ : DecidableEq ι
inst✝ : Fintype ι
this : (i : ι) → DecidableEq (α i) := fun i ↦ Classical.decEq (α i)
n : ℕ
IH :
  ∀ m < n,
    ∀ (A : (i : ι) → Finset (α i)),
      ∑ i, #(A i) = m → (f fun i ↦ ∑ j ∈ A i, g i j) = ∑ r ∈ piFinset A, f fun i ↦ g i (r i)
A : (i : ι) → Finset (α i)
h : ∑ i, #(A i) = n
Ai_empty : ∀ (i : ι), (A i).Nonempty
i₀ : ι
hi₀ : 1 < #(A i₀)
j₁ j₂ : α i₀
left✝ : j₁ ∈ A i₀
hj₂ : j₂ ∈ A i₀
right✝ : j₁ ≠ j₂
B : (a : ι) → Finset (α a) := update A i₀ (A i₀ \ {j₂})
C : (a : ι) → Finset (α a) := update A i₀ {j₂}
B_subset_A : ∀ (i : ι), B i ⊆ A i
C_subset_A : ∀ (i : ι), C i ⊆ A i
A_eq_BC : (fun i ↦ ∑ j ∈ A i, g i j) = update (fun i ↦ ∑ j ∈ A i, g i j) i₀ (∑ j ∈ B i₀, g i₀ j + ∑ j ∈ C i₀, g i₀ j)
Beq : update (fun i ↦ ∑ j ∈ A i, g i j) i₀ (∑ j ∈ B i₀, g i₀ j) = fun i ↦ ∑ j ∈ B i, g i j
i : ι
⊢ update (fun i ↦ ∑ j ∈ A i, g i j) i₀ (∑ j ∈ C i₀, g i₀ j) i = ∑ j ∈ C i, g i j
Module: Mathlib.CategoryTheory.Filtered.Basic

Goal state before:
pp: case empty
C : Type u
inst✝¹ : Category.{v, u} C
inst✝ : IsCofiltered C
O : Finset C
H : Finset ((X : C) ×' (Y : C) ×' (_ : X ∈ O) ×' (_ : Y ∈ O) ×' (X ⟶ Y))
⊢ ∃ S T, ∀ {X Y : C} (mX : X ∈ O) (mY : Y ∈ O) {f : X ⟶ Y}, ⟨X, ⟨Y, ⟨mX, ⟨mY, f⟩⟩⟩⟩ ∈ ∅ → T mX ≫ f = T mY

Tactic:
obtain ⟨S, f⟩ := inf_objs_exists O

Goal state after:
case empty
C : Type u
inst✝¹ : Category.{v, u} C
inst✝ : IsCofiltered C
O : Finset C
H : Finset ((X : C) ×' (Y : C) ×' (_ : X ∈ O) ×' (_ : Y ∈ O) ×' (X ⟶ Y))
S : C
f : ∀ {X : C}, X ∈ O → Nonempty (S ⟶ X)
⊢ ∃ S T, ∀ {X Y : C} (mX : X ∈ O) (mY : Y ∈ O) {f : X ⟶ Y}, ⟨X, ⟨Y, ⟨mX, ⟨mY, f⟩⟩⟩⟩ ∈ ∅ → T mX ≫ f = T mY
Module: Mathlib.CategoryTheory.Limits.Types.Filtered

Goal state before:
pp: J : Type v
inst✝ : Category.{w, v} J
F : J ⥤ Type u
t : Cocone F
hsurj : ∀ (x : t.pt), ∃ i xi, x = (hom (t.ι.app i)) xi
hinj :
  ∀ (i j : J) (xi : (fun X ↦ X) (F.obj i)) (xj : (fun X ↦ X) (F.obj j)),
    (hom (t.ι.app i)) xi = (hom (t.ι.app j)) xj → ∃ k f g, (hom (F.map f)) xi = (hom (F.map g)) xj
α : t.pt → J := fun x ↦ ⋯.choose
f : (x : t.pt) → F.obj (α x) := fun x ↦ ⋯.choose
hf : ∀ (x : t.pt), x = (hom (t.ι.app (α x))) (f x)
s : Cocone F
m : t.pt ⟶ s.pt
hm : ∀ (j : J), t.ι.app j ≫ m = s.ι.app j
⊢ m = ↾fun x ↦ (hom (s.ι.app (α x))) (f x)

Tactic:
by
        ext x
        dsimp
        nth_rw 1 [hf x]
        simp [← hm, comp_apply]

Goal state after: