mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.GroupTheory.Coxeter.Inversion

Goal state before:
pp: B : Type u_1
W : Type u_2
inst✝ : Group W
M : CoxeterMatrix B
cs : CoxeterSystem M W
ω : List B
j : ℕ
⊢ cs.wordProd (take j ω) * (Option.map cs.simple ω[j]?).getD 1 * (cs.wordProd (take j ω))⁻¹ *
      cs.wordProd (take (j + 1) ω ++ drop (j + 1) ω) =
    cs.wordProd (take j ω ++ drop (j + 1) ω)

Tactic:
take_add_one

Goal state after:
B : Type u_1
W : Type u_2
inst✝ : Group W
M : CoxeterMatrix B
cs : CoxeterSystem M W
ω : List B
j : ℕ
⊢ cs.wordProd (take j ω) * (Option.map cs.simple ω[j]?).getD 1 * (cs.wordProd (take j ω))⁻¹ *
      cs.wordProd (take j ω ++ ω[j]?.toList ++ drop (j + 1) ω) =
    cs.wordProd (take j ω ++ drop (j + 1) ω)
Module: Mathlib.GroupTheory.Descent

Goal state before:
pp: M : Type u_1
inst✝¹ : Monoid M
n : ℕ
h : M → ℝ
b c₀ : ℝ
hb : 1 < b
H : ∀ (x : M), b * h x - c₀ ≤ h (x ^ n)
inst✝ : Northcott h
t : M
ht : t ∈ {x | IsOfFinOrder x}
this : Finite ↥(Submonoid.powers t)
C : ℝ := ⨆ g, h ↑g
hC : ∀ g ∈ Submonoid.powers t, h g ≤ C
t₀ : ↥(Submonoid.powers t)
ht₀ : h ↑t₀ = C
⊢ C ≤ c₀ / (b - 1)

Tactic:
le_div_iff₀' (by grind)

Goal state after:
M : Type u_1
inst✝¹ : Monoid M
n : ℕ
h : M → ℝ
b c₀ : ℝ
hb : 1 < b
H : ∀ (x : M), b * h x - c₀ ≤ h (x ^ n)
inst✝ : Northcott h
t : M
ht : t ∈ {x | IsOfFinOrder x}
this : Finite ↥(Submonoid.powers t)
C : ℝ := ⨆ g, h ↑g
hC : ∀ g ∈ Submonoid.powers t, h g ≤ C
t₀ : ↥(Submonoid.powers t)
ht₀ : h ↑t₀ = C
⊢ (b - 1) * C ≤ c₀
Module: Mathlib.GroupTheory.DivisibleHull

Goal state before:
pp: case e'_2
M✝ : Type u_1
inst✝¹ : AddCommMonoid M✝
M : Type u_2
inst✝ : AddCommGroup M
a b : ℚ
m : M
s : ℕ+
this :
  ((a + b).num * ↑a.den * ↑b.den * (↑↑s * ↑↑s)) • m =
    ((a.num * ↑b.den + b.num * ↑a.den) * ↑(a + b).den * (↑↑s * ↑↑s)) • m
⊢ ↑1 • ↑(⟨a.den, ⋯⟩ * s * (⟨b.den, ⋯⟩ * s)) • (a + b).num • m = ((a + b).num * ↑a.den * ↑b.den * (↑↑s * ↑↑s)) • m

Tactic:
simp [← natCast_zsmul, smul_smul, ← add_smul]

Goal state after:
case e'_2
M✝ : Type u_1
inst✝¹ : AddCommMonoid M✝
M : Type u_2
inst✝ : AddCommGroup M
a b : ℚ
m : M
s : ℕ+
this :
  ((a + b).num * ↑a.den * ↑b.den * (↑↑s * ↑↑s)) • m =
    ((a.num * ↑b.den + b.num * ↑a.den) * ↑(a + b).den * (↑↑s * ↑↑s)) • m
⊢ (↑a.den * ↑↑s * (↑b.den * ↑↑s) * (a + b).num) • m = ((a + b).num * ↑a.den * ↑b.den * (↑↑s * ↑↑s)) • m
Module: Mathlib.GroupTheory.DivisibleHull

Goal state before:
pp: case e'_3
M✝ : Type u_1
inst✝¹ : AddCommMonoid M✝
M : Type u_2
inst✝ : AddCommGroup M
a b : ℚ
m : M
s : ℕ+
this :
  ((a + b).num * ↑a.den * ↑b.den * (↑↑s * ↑↑s)) • m =
    ((a.num * ↑b.den + b.num * ↑a.den) * ↑(a + b).den * (↑↑s * ↑↑s)) • m
⊢ ↑1 • ↑(⟨(a + b).den, ⋯⟩ * s) • (↑(⟨b.den, ⋯⟩ * s) • a.num • m + ↑(⟨a.den, ⋯⟩ * s) • b.num • m) =
    ((a.num * ↑b.den + b.num * ↑a.den) * ↑(a + b).den * (↑↑s * ↑↑s)) • m

Tactic:
simp [← natCast_zsmul, smul_smul, ← add_smul]

Goal state after:
case e'_3
M✝ : Type u_1
inst✝¹ : AddCommMonoid M✝
M : Type u_2
inst✝ : AddCommGroup M
a b : ℚ
m : M
s : ℕ+
this :
  ((a + b).num * ↑a.den * ↑b.den * (↑↑s * ↑↑s)) • m =
    ((a.num * ↑b.den + b.num * ↑a.den) * ↑(a + b).den * (↑↑s * ↑↑s)) • m
⊢ (↑(a + b).den * ↑↑s * (↑b.den * ↑↑s * a.num + ↑a.den * ↑↑s * b.num)) • m =
    ((a.num * ↑b.den + b.num * ↑a.den) * ↑(a + b).den * (↑↑s * ↑↑s)) • m
Module: Mathlib.GroupTheory.DivisibleHull

Goal state before:
pp: M✝ : Type u_1
inst✝³ : AddCommMonoid M✝
M : Type u_2
inst✝² : AddCommMonoid M
inst✝¹ : LinearOrder M
inst✝ : IsOrderedCancelAddMonoid M
a b c : DivisibleHull M
h : b < c
⊢ a + b < a + c

Tactic:
induction a with | mk ma sa
    induction b with | mk mb sb
    induction c with | mk mc sc
    simp_rw [mk_add_mk]
    rw [mk_lt_mk] at ⊢ h
    simp_rw [PNat.mul_coe, mul_smul, smul_add, smul_smul]
    have := add_lt_add_right (nsmul_lt_nsmul_right (sa * sa).ne_zero h) ((sa * sb * sc.val) • ma)
    simp_rw [PNat.mul_coe, smul_smul] at this
    convert! this using 3 <;> ring

Goal state after:
Module: Mathlib.GroupTheory.Schreier

Goal state before:
pp: case refine_3
G : Type u_1
inst✝ : Group G
H : Subgroup G
R S : Set G
hR : IsComplement (↑H) R
hR1 : 1 ∈ R
hS : closure S = ⊤
f : G → ↑R := hR.toRightFun
U : Set G := (fun g ↦ g * (↑(f g))⁻¹) '' (R * S)
g : G
x✝ : g ∈ ⊤
s : G
hs : s ∈ S
u : G
hu : u ∈ ↑(closure U)
r : G
hr : r ∈ R
⊢ ↑(f (↑(f (↑⟨r, hr⟩ * s⁻¹)) * s)) = ↑⟨r, hr⟩

Tactic:
← Subtype.ext_iff,

Goal state after:
case refine_3
G : Type u_1
inst✝ : Group G
H : Subgroup G
R S : Set G
hR : IsComplement (↑H) R
hR1 : 1 ∈ R
hS : closure S = ⊤
f : G → ↑R := hR.toRightFun
U : Set G := (fun g ↦ g * (↑(f g))⁻¹) '' (R * S)
g : G
x✝ : g ∈ ⊤
s : G
hs : s ∈ S
u : G
hu : u ∈ ↑(closure U)
r : G
hr : r ∈ R
⊢ f (↑(f (↑⟨r, hr⟩ * s⁻¹)) * s) = ⟨r, hr⟩
Module: Mathlib.GroupTheory.Transfer

Goal state before:
pp: case neg.inl
G : Type u_3
inst✝¹ : Group G
inst✝ : Finite G
P : Sylow (Nat.card G).minFac G
hP : IsCyclic ↥↑P
hn : ¬Nat.card G = 1
this : Fact (Nat.Prime (Nat.card G).minFac)
key : (centralizer ↑↑P).relIndex (normalizer ↑↑P) ∣ Nat.card (MulAut ↥↑P)
k : ℕ
hk : Nat.card ↥↑P = (Nat.card G).minFac ^ k
h0 : k = 0
⊢ ((centralizer ↑P).relIndex (normalizer ↑P)).Coprime (Nat.totient 1)

Tactic:
Nat.totient_one

Goal state after:
case neg.inl
G : Type u_3
inst✝¹ : Group G
inst✝ : Finite G
P : Sylow (Nat.card G).minFac G
hP : IsCyclic ↥↑P
hn : ¬Nat.card G = 1
this : Fact (Nat.Prime (Nat.card G).minFac)
key : (centralizer ↑↑P).relIndex (normalizer ↑↑P) ∣ Nat.card (MulAut ↥↑P)
k : ℕ
hk : Nat.card ↥↑P = (Nat.card G).minFac ^ k
h0 : k = 0
⊢ ((centralizer ↑P).relIndex (normalizer ↑P)).Coprime 1
Module: Mathlib.GroupTheory.Nilpotent

Goal state before:
pp: G : Type u_1
inst✝¹ : Group G
N : Subgroup G
inst✝ : N.Normal
x✝ : G
⊢ x✝ ∈ N.upperCentralSeriesStep ↔ x✝ ∈ comap (mk' N) (center (G ⧸ N))

Tactic:
rw [mem_comap, mem_center_iff, forall_mk]

Goal state after:
G : Type u_1
inst✝¹ : Group G
N : Subgroup G
inst✝ : N.Normal
x✝ : G
⊢ x✝ ∈ N.upperCentralSeriesStep ↔ ∀ (x : G), ↑x * (mk' N) x✝ = (mk' N) x✝ * ↑x
Module: Mathlib.GroupTheory.FreeGroup.NielsenSchreier

Goal state before:
pp: case refine_2
G A : Type u
inst✝³ : Group G
inst✝² : IsFreeGroup G
inst✝¹ : MulAction G A
X : Type u
inst✝ : Group X
f : Labelling (Generators (ActionCategory G A)) X
f' : IsFreeGroup.Generators G → (A → X) ⋊[mulAutArrow] G := fun e ↦ ⟨fun b ↦ f ⟨e, ⋯⟩, IsFreeGroup.of e⟩
F' : G →* (A → X) ⋊[mulAutArrow] G
hF' : ∀ (a : IsFreeGroup.Generators G), F' (IsFreeGroup.of a) = f' a
uF' :
  ∀ (y : G →* (A → X) ⋊[mulAutArrow] G),
    (fun F ↦ ∀ (a : IsFreeGroup.Generators G), F (IsFreeGroup.of a) = f' a) y → y = F'
⊢ (fun F ↦ ∀ (a b : Generators (ActionCategory G A)) (g : a ⟶ b), F.map ⟨IsFreeGroup.of ↑g, ⋯⟩ = f g) (uncurry F' ⋯)

Tactic:
rintro ⟨⟨⟩, a : A⟩ ⟨⟨⟩, b⟩ ⟨e, h : IsFreeGroup.of e • a = b⟩

Goal state after:
case refine_2
G A : Type u
inst✝³ : Group G
inst✝² : IsFreeGroup G
inst✝¹ : MulAction G A
X : Type u
inst✝ : Group X
f : Labelling (Generators (ActionCategory G A)) X
f' : IsFreeGroup.Generators G → (A → X) ⋊[mulAutArrow] G := fun e ↦ ⟨fun b ↦ f ⟨e, ⋯⟩, IsFreeGroup.of e⟩
F' : G →* (A → X) ⋊[mulAutArrow] G
hF' : ∀ (a : IsFreeGroup.Generators G), F' (IsFreeGroup.of a) = f' a
uF' :
  ∀ (y : G →* (A → X) ⋊[mulAutArrow] G),
    (fun F ↦ ∀ (a : IsFreeGroup.Generators G), F (IsFreeGroup.of a) = f' a) y → y = F'
a : A
b : (actionAsFunctor G A).obj PUnit.unit
e : IsFreeGroup.Generators G
h : IsFreeGroup.of e • a = b
⊢ (uncurry F' ⋯).map ⟨IsFreeGroup.of ↑⟨e, h⟩, ⋯⟩ = f ⟨e, h⟩
Module: Mathlib.GroupTheory.GroupAction.Blocks

Goal state before:
pp: G : Type u_1
inst✝¹ : Group G
X : Type u_2
inst✝ : MulAction G X
B : Set X
g : G
hB : IsBlock G B
⊢ IsBlock G (g • B)

Tactic:
← isBlock_top

Goal state after:
G : Type u_1
inst✝¹ : Group G
X : Type u_2
inst✝ : MulAction G X
B : Set X
g : G
hB : IsBlock (↥⊤) B
⊢ IsBlock (↥⊤) (g • B)
Module: Mathlib.GroupTheory.GroupAction.Blocks

Goal state before:
pp: case h
G : Type u_1
inst✝¹ : Group G
X : Type u_2
inst✝ : MulAction G X
N : Subgroup G
nN : N.Normal
a : X
g k : G
hk : k ∈ N
⊢ g • (g⁻¹ * k * g) • a = k • g • a

Tactic:
simp only [← smul_smul, smul_inv_smul]

Goal state after:
Module: Mathlib.GroupTheory.GroupAction.Blocks

Goal state before:
pp: case inl
G : Type u_1
inst✝³ : Group G
X : Type u_2
inst✝² : MulAction G X
inst✝¹ : IsPretransitive G X
B : Set X
inst✝ : Finite X
hB : IsBlock G B
hB' : Nat.card X < 2 * (orbit G B).ncard
h : B = ∅
⊢ ∅.ncard < 2

Tactic:
Set.ncard_empty

Goal state after:
case inl
G : Type u_1
inst✝³ : Group G
X : Type u_2
inst✝² : MulAction G X
inst✝¹ : IsPretransitive G X
B : Set X
inst✝ : Finite X
hB : IsBlock G B
hB' : Nat.card X < 2 * (orbit G B).ncard
h : B = ∅
⊢ 0 < 2
Module: Mathlib.GroupTheory.GroupAction.SubMulAction.OfStabilizer

Goal state before:
pp: G : Type u_1
inst✝¹ : Group G
α : Type u_2
inst✝ : MulAction G α
a : α
g : ↥(stabilizer G a)
x : α
hgx : x = g⁻¹ • a
⊢ g • a = a

Tactic:
exact g.prop

Goal state after:
Module: Mathlib.GroupTheory.GroupAction.SubMulAction.OfStabilizer

Goal state before:
pp: case left
G : Type u_1
inst✝¹ : Group G
α : Type u_2
inst✝ : MulAction G α
g : G
a b : α
hg : b = g • a
⊢ Function.Injective ⇑(conjMap hg)

Tactic:
rintro ⟨x, hx⟩ ⟨y, hy⟩ hxy
    simp only [Subtype.mk_eq_mk]
    apply (MulAction.injective g)
    rwa [← SetLike.coe_eq_coe, conjMap_apply] at hxy

Goal state after:
Module: Mathlib.SetTheory.Cardinal.Embedding

Goal state before:
pp: case h
α : Type u_1
n : ℕ
s : Set α
inst✝ : Finite ↑s
hs : ↑s.ncard + ↑n ≤ ENat.card α
y : Fin n ↪ ↑sᶜ
⊢ Disjoint s (range ⇑(y.trans (subtype fun x ↦ x ∈ sᶜ)))

Tactic:
Set.disjoint_right

Goal state after:
case h
α : Type u_1
n : ℕ
s : Set α
inst✝ : Finite ↑s
hs : ↑s.ncard + ↑n ≤ ENat.card α
y : Fin n ↪ ↑sᶜ
⊢ ∀ ⦃a : α⦄, a ∈ range ⇑(y.trans (subtype fun x ↦ x ∈ sᶜ)) → a ∉ s
Module: Mathlib.GroupTheory.SpecificGroups.Alternating

Goal state before:
pp: α : Type u_1
inst✝¹ : Fintype α
inst✝ : DecidableEq α
G : Subgroup (Perm α)
hG : G.index = 2
a✝ : Nontrivial α
a b : α
hab : a ≠ b
habG : swap a b ∉ G
g✝ g : Perm α
x y : α
hxy : x ≠ y
ih : g ∈ G ↔ g ∈ alternatingGroup α
⊢ swap x y * g ∈ G ↔ swap x y * g ∈ alternatingGroup α

Tactic:
rw [mul_mem_iff_of_index_two hG, mul_mem_iff_of_index_two alternatingGroup.index_eq_two, ih]

Goal state after:
α : Type u_1
inst✝¹ : Fintype α
inst✝ : DecidableEq α
G : Subgroup (Perm α)
hG : G.index = 2
a✝ : Nontrivial α
a b : α
hab : a ≠ b
habG : swap a b ∉ G
g✝ g : Perm α
x y : α
hxy : x ≠ y
ih : g ∈ G ↔ g ∈ alternatingGroup α
⊢ (swap x y ∈ G ↔ g ∈ alternatingGroup α) ↔ (swap x y ∈ alternatingGroup α ↔ g ∈ alternatingGroup α)
Module: Mathlib.GroupTheory.GroupAction.MultipleTransitivity

Goal state before:
pp: case h.inr
G : Type u_1
α : Type u_2
inst✝² : Group G
inst✝¹ : MulAction G α
inst✝ : IsPretransitive G α
n : ℕ
a : α
hn : IsMultiplyPretransitive (↥(stabilizer G a)) (↥(ofStabilizer G a)) n
x y : Fin n.succ ↪ α
gx : G
x1 : Fin n ↪ ↥(ofStabilizer G a)
hgx : gx • x = snoc x1
gy : G
y1 : Fin n ↪ ↥(ofStabilizer G a)
hgy : gy • y = snoc y1
g : ↥(stabilizer G a)
hg : g • x1 = y1
⊢ ↑g • a = a

Tactic:
exact g.prop

Goal state after:
Module: Mathlib.GroupTheory.GroupAction.SubMulAction.OfFixingSubgroup

Goal state before:
pp: M : Type u_1
α : Type u_2
inst✝¹ : Group M
inst✝ : MulAction M α
a : α
s : Set α
m : M
⊢ m ∈ fixingSubgroup M (insert a s) ↔ m • a = a ∧ m ∈ fixingSubgroup M s

Tactic:
simp [mem_fixingSubgroup_iff]

Goal state after:
Module: Mathlib.GroupTheory.GroupAction.MultiplePrimitivity

Goal state before:
pp: M : Type u_1
α : Type u_2
inst✝² : Group M
inst✝¹ : MulAction M α
n : ℕ
hα : ↑n.succ ≤ ENat.card α
inst✝ : IsMultiplyPretransitive M α n.succ
⊢ IsMultiplyPreprimitive M α n

Tactic:
rcases Nat.eq_zero_or_pos n with hn | hn
  · rw [hn]
    exact is_zero_preprimitive M α
  rw [isMultiplyPreprimitive_iff]
  constructor
  · exact isMultiplyPretransitive_of_le' (Nat.le_succ n) hα
  · intro s hs
    obtain ⟨m, hm⟩ := Nat.exists_eq_add_of_le hn
    apply isPreprimitive_of_is_two_pretransitive
    have hs' : s.encard = m := by
      simp only [hm, Nat.succ_eq_add_one, zero_add, add_comm 1] at hs
      exact ENat.add_left_injective_of_ne_top ENat.one_ne_top hs
    have : Finite s := Set.finite_of_encard_eq_coe hs'
    apply ofFixingSubgroup.isMultiplyPretransitive (G := M) s (n := n.succ)
    simp [Set.ncard, hs', hm, add_comm 1]

Goal state after:
Module: Mathlib.GroupTheory.GroupAction.Period

Goal state before:
pp: α : Type v
M : Type u
inst✝¹ : Monoid M
inst✝ : MulAction M α
m : M
a : α
⊢ m ^ orderOf m • a = a

Tactic:
pow_orderOf_eq_one,

Goal state after:
α : Type v
M : Type u
inst✝¹ : Monoid M
inst✝ : MulAction M α
m : M
a : α
⊢ 1 • a = a
Module: Mathlib.GroupTheory.GroupAction.MultipleTransitivity

Goal state before:
pp: α : Type u_1
inst✝¹ : Fintype α
inst✝ : DecidableEq α
h : 3 ≤ Nat.card α
this : IsMultiplyPretransitive (↥(alternatingGroup α)) α (Nat.card α - 2) := ⋯
⊢ 1 ≤ Nat.card α - 2

Tactic:
rwa [← add_le_add_iff_right 2, Nat.sub_add_cancel (le_trans (by norm_num) h)]

Goal state after:
Module: Mathlib.GroupTheory.SpecificGroups.Alternating.MaximalSubgroups

Goal state before:
pp: case inl
α : Type u_1
inst✝¹ : Fintype α
inst✝ : DecidableEq α
s : Set α
hα : 4 < Nat.card α
hs : 2 < s.ncard
⊢ ∃ g ∈ stabilizer (Perm α) s, g.IsThreeCycle

Tactic:
exact exists_mem_stabilizer_isThreeCycle_of_two_lt_ncard hs

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

Goal state before:
pp: α : Type u_2
s B : Set α
G : Subgroup (Perm α)
hB : IsBlock (↥G) B
hB_ss_sc : B ⊂ s
hG : stabilizer (Perm α) s ≤ G
k : Perm α
hk : k ∈ stabilizer (Perm α) s
⊢ ∃ a, toPerm a = toPerm ⟨k, hk⟩

Tactic:
let h : G := ⟨k, hG hk⟩

Goal state after:
α : Type u_2
s B : Set α
G : Subgroup (Perm α)
hB : IsBlock (↥G) B
hB_ss_sc : B ⊂ s
hG : stabilizer (Perm α) s ≤ G
k : Perm α
hk : k ∈ stabilizer (Perm α) s
h : ↥G := ⟨k, ⋯⟩
⊢ ∃ a, toPerm a = toPerm ⟨k, hk⟩
Module: Mathlib.GroupTheory.Perm.MaximalSubgroups

Goal state before:
pp: M : Type u_1
α : Type u_2
inst✝³ : Group M
inst✝² : MulAction M α
s : Set α
inst✝¹ : Finite α
inst✝ : IsMultiplyPretransitive M α (s.ncard + 1)
G : Subgroup M
hG : stabilizer M s ≤ G
B : Set α
hBs : ¬B ⊆ s
hBsc : ¬B ⊆ sᶜ
hB : IsBlock (↥G) B
a : α
ha : a ∈ B
ha' : a ∈ s
b : α
hb : b ∈ B
hb' : b ∈ sᶜ
k : M
hk✝ : k ∈ fixingSubgroup M s
hk : ∀ y ∈ s, k • y = y
hx' : ⟨k, hk✝⟩ • b ∈ sᶜ
⊢ k • a ∈ ⟨k, ⋯⟩ • B

Tactic:
exact Set.smul_mem_smul_set ha

Goal state after:
Module: Mathlib.GroupTheory.IsSubnormal

Goal state before:
pp: case succ
G : Type u_1
inst✝ : Group G
n : ℕ
ih :
  ∀ {H : Subgroup G},
    (∃ f, Monotone f ∧ (∀ (i : ℕ), ((f i).subgroupOf (f (i + 1))).Normal) ∧ f 0 = H ∧ f n = ⊤) → H.IsSubnormal
⊢ ∀ {H : Subgroup G},
    (∃ f, Monotone f ∧ (∀ (i : ℕ), ((f i).subgroupOf (f (i + 1))).Normal) ∧ f 0 = H ∧ f (n + 1) = ⊤) → H.IsSubnormal

Tactic:
rintro J ⟨F, hF, H_le, rfl, ih1⟩
      refine step _ _ (hF <| Nat.le_add_right 0 1) ?_ (H_le _)
      refine ih ⟨fun n ↦ F (n + 1), ?_⟩
      grind only [Monotone, monotone_iff_forall_lt]

Goal state after:
Module: Mathlib.GroupTheory.MonoidLocalization.UniqueFactorization

Goal state before:
pp: M : Type u_1
N : Type u_2
inst✝¹ : CommMonoidWithZero M
inst✝ : CommMonoidWithZero N
S : Submonoid M
f : S.LocalizationMap N
m : M
prime : Prime m
n0 : f m ≠ 0
nu : ¬IsUnit (f m)
n₁ n₂ : N
dvd : f m ∣ n₁ * n₂
m₁ : M
s₁ : ↥S
eq₁ : n₁ * f ↑(m₁, s₁).2 = f (m₁, s₁).1
m₂ : M
s₂ : ↥S
eq₂ : n₂ * f ↑(m₂, s₂).2 = f (m₂, s₂).1
this : ∃ s ∈ S, m ∣ s * ((m₁, s₁).1 * (m₂, s₂).1)
⊢ f m ∣ n₁ ∨ f m ∣ n₂

Tactic:
have ⟨s, hs, dvd⟩ := this

Goal state after:
M : Type u_1
N : Type u_2
inst✝¹ : CommMonoidWithZero M
inst✝ : CommMonoidWithZero N
S : Submonoid M
f : S.LocalizationMap N
m : M
prime : Prime m
n0 : f m ≠ 0
nu : ¬IsUnit (f m)
n₁ n₂ : N
dvd✝ : f m ∣ n₁ * n₂
m₁ : M
s₁ : ↥S
eq₁ : n₁ * f ↑(m₁, s₁).2 = f (m₁, s₁).1
m₂ : M
s₂ : ↥S
eq₂ : n₂ * f ↑(m₂, s₂).2 = f (m₂, s₂).1
this : ∃ s ∈ S, m ∣ s * ((m₁, s₁).1 * (m₂, s₂).1)
s : M
hs : s ∈ S
dvd : m ∣ s * ((m₁, s₁).1 * (m₂, s₂).1)
⊢ f m ∣ n₁ ∨ f m ∣ n₂
Module: Mathlib.GroupTheory.MonoidLocalization.Order

Goal state before:
pp: α : Type u_1
inst✝² : CommMonoid α
inst✝¹ : PartialOrder α
inst✝ : IsOrderedCancelMonoid α
s : Submonoid α
a₁ b₁ : α
a₂ b₂ : ↥s
a✝ b✝ c✝ : Localization s
a b c : α × ↥s
hab : ↑b.2 * a.1 ≤ ↑a.2 * b.1
hbc : ↑c.2 * b.1 ≤ ↑b.2 * c.1
⊢ α

pp: α : Type u_1
inst✝² : CommMonoid α
inst✝¹ : PartialOrder α
inst✝ : IsOrderedCancelMonoid α
s : Submonoid α
a₁ b₁ : α
a₂ b₂ : ↥s
a✝ b✝ c✝ : Localization s
a b c : α × ↥s
hab : ↑b.2 * a.1 ≤ ↑a.2 * b.1
hbc : ↑c.2 * b.1 ≤ ↑b.2 * c.1
⊢ ?m.116 * (↑c.2 * a.1) ≤ ?m.116 * (↑a.2 * c.1)

Tactic:
· exact ↑b.2

Goal state after:
α : Type u_1
inst✝² : CommMonoid α
inst✝¹ : PartialOrder α
inst✝ : IsOrderedCancelMonoid α
s : Submonoid α
a₁ b₁ : α
a₂ b₂ : ↥s
a✝ b✝ c✝ : Localization s
a b c : α × ↥s
hab : ↑b.2 * a.1 ≤ ↑a.2 * b.1
hbc : ↑c.2 * b.1 ≤ ↑b.2 * c.1
⊢ ↑b.2 * (↑c.2 * a.1) ≤ ↑b.2 * (↑a.2 * c.1)
Module: Mathlib.GroupTheory.MonoidLocalization.UniqueFactorization

Goal state before:
pp: case inl
M : Type u_1
N : Type u_2
inst✝¹ : CommMonoidWithZero M
inst✝ : CommMonoidWithZero N
S : Submonoid M
f : S.LocalizationMap N
m : M
prime : Prime m
n0 : f m ≠ 0
nu : ¬IsUnit (f m)
n₁ n₂ : N
dvd✝¹ : f m ∣ n₁ * n₂
m₁ : M
s₁ : ↥S
eq₁ : n₁ * f ↑(m₁, s₁).2 = f (m₁, s₁).1
m₂ : M
s₂ : ↥S
eq₂ : n₂ * f ↑(m₂, s₂).2 = f (m₂, s₂).1
this✝ : ∃ s ∈ S, m ∣ s * ((m₁, s₁).1 * (m₂, s₂).1)
s : M
hs : s ∈ S
dvd✝ : m ∣ s * (m₁, s₁).1 * (m₂, s₂).1
dvd : m ∣ s * (m₁, s₁).1
this : f m ∣ f s * f (m₁, s₁).1
⊢ f m ∣ n₁ ∨ f m ∣ n₂

Tactic:
(f.map_units ⟨s, hs⟩).dvd_mul_left,

Goal state after:
case inl
M : Type u_1
N : Type u_2
inst✝¹ : CommMonoidWithZero M
inst✝ : CommMonoidWithZero N
S : Submonoid M
f : S.LocalizationMap N
m : M
prime : Prime m
n0 : f m ≠ 0
nu : ¬IsUnit (f m)
n₁ n₂ : N
dvd✝¹ : f m ∣ n₁ * n₂
m₁ : M
s₁ : ↥S
eq₁ : n₁ * f ↑(m₁, s₁).2 = f (m₁, s₁).1
m₂ : M
s₂ : ↥S
eq₂ : n₂ * f ↑(m₂, s₂).2 = f (m₂, s₂).1
this✝ : ∃ s ∈ S, m ∣ s * ((m₁, s₁).1 * (m₂, s₂).1)
s : M
hs : s ∈ S
dvd✝ : m ∣ s * (m₁, s₁).1 * (m₂, s₂).1
dvd : m ∣ s * (m₁, s₁).1
this : f m ∣ f (m₁, s₁).1
⊢ f m ∣ n₁ ∨ f m ∣ n₂
Module: Mathlib.GroupTheory.Perm.Cycle.PossibleTypes

Goal state before:
pp: case mp.right
α : Type u_1
inst✝¹ : DecidableEq α
inst✝ : Fintype α
m : Multiset ℕ
g : Perm α
hg : g.cycleType = m
⊢ ∀ a ∈ m, 2 ≤ a

Tactic:
· intro a
      rw [← hg]
      exact Equiv.Perm.two_le_of_mem_cycleType

Goal state after:
Module: Mathlib.GroupTheory.HNNExtension

Goal state before:
pp: G : Type u_1
inst✝ : Group G
A B : Subgroup G
φ : ↥A ≃* ↥B
d : TransversalPair G A B
a₁✝ a₂✝ : G
h : ((fun x1 x2 ↦ x1 • x2) ∘ ⇑of) a₁✝ = ((fun x1 x2 ↦ x1 • x2) ∘ ⇑of) a₂✝
w : NormalWord d
⊢ a₁✝ • w = a₂✝ • w

Tactic:
by simp_all [funext_iff, of_smul_eq_smul]

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

Goal state before:
pp: α : Type u_1
inst✝¹ : DecidableEq α
inst✝ : Fintype α
g : Perm α
a : g.Basis
τ : ↥(range_toPermHom' g)
x : α
c : ↥g.cycleFactorsFinset
hx : x ∈ (↑c).support
m : ℤ
hm : (g ^ m) (a c) = x
hx' : ↑c = g.cycleOf x
hx'' : g.cycleOf x ∈ g.cycleFactorsFinset
n : ℕ := Nat.find ⋯
hn : (g ^ ↑n) (a c) = x
⊢ a.ofPermHomFun τ x = (g ^ ↑n) (a (↑τ c))

Tactic:
simp only [ofPermHomFun, dif_pos hx'']

Goal state after:
α : Type u_1
inst✝¹ : DecidableEq α
inst✝ : Fintype α
g : Perm α
a : g.Basis
τ : ↥(range_toPermHom' g)
x : α
c : ↥g.cycleFactorsFinset
hx : x ∈ (↑c).support
m : ℤ
hm : (g ^ m) (a c) = x
hx' : ↑c = g.cycleOf x
hx'' : g.cycleOf x ∈ g.cycleFactorsFinset
n : ℕ := Nat.find ⋯
hn : (g ^ ↑n) (a c) = x
⊢ (g ^ Nat.find ⋯) (a (↑τ ⟨g.cycleOf x, hx''⟩)) = (g ^ ↑n) (a (↑τ c))
Module: Mathlib.GroupTheory.ResiduallyFinite

Goal state before:
pp: G : Type u_1
inst✝ : Group G
h : ∀ (g : G), g ≠ 1 → ∃ H x, ∃ (_ : Finite H), ∃ f, f g ≠ 1
g : G
hg : g ≠ 1
w✝² : Type u
w✝¹ : Group w✝²
w✝ : Finite w✝²
f : G →* w✝²
hf : f g ≠ 1
⊢ ∃ H, H.FiniteIndex ∧ g ∉ H

Tactic:
exact ⟨f.ker, Subgroup.finiteIndex_ker f, by simpa using hf⟩

Goal state after:
Module: Mathlib.GroupTheory.SchurZassenhaus

Goal state before:
pp: G : Type u_1
inst✝³ : Group G
H : Subgroup G
inst✝² : IsMulCommutative ↥H
inst✝¹ : H.FiniteIndex
α β : H.LeftTransversal
inst✝ : H.Normal
h : ↥H
this : Fintype (G ⧸ H) := fintypeQuotientOfFiniteIndex
q : G ⧸ H
x✝ : q ∈ Finset.univ
⊢ ↑(⋯.leftQuotientEquiv ((op ↑h)⁻¹ • q)) = ↑(⋯.leftQuotientEquiv q)

Tactic:
← Subtype.ext_iff,

Goal state after:
G : Type u_1
inst✝³ : Group G
H : Subgroup G
inst✝² : IsMulCommutative ↥H
inst✝¹ : H.FiniteIndex
α β : H.LeftTransversal
inst✝ : H.Normal
h : ↥H
this : Fintype (G ⧸ H) := fintypeQuotientOfFiniteIndex
q : G ⧸ H
x✝ : q ∈ Finset.univ
⊢ ⋯.leftQuotientEquiv ((op ↑h)⁻¹ • q) = ⋯.leftQuotientEquiv q
Module: Mathlib.GroupTheory.SchurZassenhaus

Goal state before:
pp: G : Type u
inst✝¹ : Group G
inst✝ : ⊥.Normal
h1 : (Nat.card ↥⊥).Coprime ⊥.index
h3 : ∀ (H : Subgroup G), ¬⊥.IsComplement' H
⊢ False

Tactic:
exact h3 ⊤ isComplement'_bot_top

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

Goal state before:
pp: case neg
α : Type u_1
inst✝¹ : DecidableEq α
inst✝ : Fintype α
g : Perm α
u : Perm ↑(Function.fixedPoints ⇑g)
v : (c : ↥g.cycleFactorsFinset) → ↥(zpowers ↑c)
x : α
hx : x ∈ ((noncommPiCoprod ⋯) (u, v).2).support
⊢ x ∈ g.support

Tactic:
obtain ⟨a, -, ha⟩ := mem_support_of_mem_noncommProd_support
      (comm := fun a ha b hb h ↦ g.pairwise_commute_of_mem_zpowers h (v a) (v b) (v a).2 (v b).2) hx

Goal state after:
case neg
α : Type u_1
inst✝¹ : DecidableEq α
inst✝ : Fintype α
g : Perm α
u : Perm ↑(Function.fixedPoints ⇑g)
v : (c : ↥g.cycleFactorsFinset) → ↥(zpowers ↑c)
x : α
hx : x ∈ ((noncommPiCoprod ⋯) (u, v).2).support
a : ↥g.cycleFactorsFinset
ha : x ∈ (↑(v a)).support
⊢ x ∈ g.support
Module: Mathlib.GroupTheory.PushoutI

Goal state before:
pp: ι : Type u_1
G : ι → Type u_2
H : Type u_3
inst✝³ : (i : ι) → Group (G i)
inst✝² : Group H
φ : (i : ι) → H →* G i
d : Transversal φ
inst✝¹ : DecidableEq ι
inst✝ : (i : ι) → DecidableEq (G i)
i : ι
h₁ : H
w₂ : Word G
h₂ : H
hw₂ : ∀ (i : ι) (g : G i), ⟨i, g⟩ ∈ w₂.toList → g ∈ d.set i
hw₁✝ :
  ∀ (i_1 : ι) (g : G i_1), ⟨i_1, g⟩ ∈ (((CoprodI.of ((φ i) h₁))⁻¹ * CoprodI.of ((φ i) h₂)) • w₂).toList → g ∈ d.set i_1
hw₁ : ∀ (i_1 : ι) (g : G i_1), ⟨i_1, g⟩ ∈ (CoprodI.of ((φ i) (h₁⁻¹ * h₂)) • w₂).toList → g ∈ d.set i_1
⊢ { toWord := ((CoprodI.of ((φ i) h₁))⁻¹ * CoprodI.of ((φ i) h₂)) • w₂, head := h₁, normalized := hw₁✝ } =
    { toWord := w₂, head := h₂, normalized := hw₂ }

Tactic:
have : h₁⁻¹ * h₂ = 1 := eq_one_of_smul_normalized w₂ (h₁⁻¹ * h₂) hw₂ hw₁

Goal state after:
ι : Type u_1
G : ι → Type u_2
H : Type u_3
inst✝³ : (i : ι) → Group (G i)
inst✝² : Group H
φ : (i : ι) → H →* G i
d : Transversal φ
inst✝¹ : DecidableEq ι
inst✝ : (i : ι) → DecidableEq (G i)
i : ι
h₁ : H
w₂ : Word G
h₂ : H
hw₂ : ∀ (i : ι) (g : G i), ⟨i, g⟩ ∈ w₂.toList → g ∈ d.set i
hw₁✝ :
  ∀ (i_1 : ι) (g : G i_1), ⟨i_1, g⟩ ∈ (((CoprodI.of ((φ i) h₁))⁻¹ * CoprodI.of ((φ i) h₂)) • w₂).toList → g ∈ d.set i_1
hw₁ : ∀ (i_1 : ι) (g : G i_1), ⟨i_1, g⟩ ∈ (CoprodI.of ((φ i) (h₁⁻¹ * h₂)) • w₂).toList → g ∈ d.set i_1
this : h₁⁻¹ * h₂ = 1
⊢ { toWord := ((CoprodI.of ((φ i) h₁))⁻¹ * CoprodI.of ((φ i) h₂)) • w₂, head := h₁, normalized := hw₁✝ } =
    { toWord := w₂, head := h₂, normalized := hw₂ }
Module: Mathlib.GroupTheory.SchurZassenhaus

Goal state before:
pp: case pos
G : Type u
inst✝¹ : Group G
N : Subgroup G
inst✝ : N.Normal
hN : (Nat.card ↥N).Coprime N.index
hN1 : ¬Nat.card ↥N = 0
hN2 : N.index = 0
⊢ ∃ H, N.IsComplement' H

Tactic:
rw [hN2, Nat.coprime_zero_right, Nat.card_eq_one_iff_unique] at hN
    have := hN.1
    rw [N.eq_bot_of_subsingleton]
    exact ⟨⊤, isComplement'_bot_top⟩

Goal state after:
Module: Mathlib.GroupTheory.SpecificGroups.Alternating.KleinFour

Goal state before:
pp: α : Type u_1
inst✝¹ : DecidableEq α
inst✝ : Fintype α
hα4 : Nat.card α = 4
S : Sylow 2 ↥(alternatingGroup α)
⊢ ↑S = kleinFour α

Tactic:
rw [kleinFour, ← Subgroup.closure_insert_one,
    ← Set.singleton_union, ← coe_two_sylow_of_card_eq_four hα4]

Goal state after:
α : Type u_1
inst✝¹ : DecidableEq α
inst✝ : Fintype α
hα4 : Nat.card α = 4
S : Sylow 2 ↥(alternatingGroup α)
⊢ ↑S = Subgroup.closure ↑?m.28

α : Type u_1
inst✝¹ : DecidableEq α
inst✝ : Fintype α
hα4 : Nat.card α = 4
S : Sylow 2 ↥(alternatingGroup α)
⊢ Sylow 2 ↥(alternatingGroup α)