mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.RingTheory.Invariant.Galois

Goal state before:
pp: A : Type u_1
K : Type u_2
L : Type u_3
B : Type u_4
inst✝¹⁵ : CommRing A
inst✝¹⁴ : CommRing B
inst✝¹³ : Field K
inst✝¹² : Field L
inst✝¹¹ : Algebra A K
inst✝¹⁰ : Algebra B L
inst✝⁹ : IsFractionRing A K
inst✝⁸ : IsFractionRing B L
inst✝⁷ : Algebra A B
inst✝⁶ : Algebra K L
inst✝⁵ : Algebra A L
inst✝⁴ : IsScalarTower A K L
inst✝³ : IsScalarTower A B L
inst✝² : IsIntegrallyClosed A
inst✝¹ : IsIntegralClosure B A L
inst✝ : FiniteDimensional K L
h✝ : IsGalois K L
h : IntermediateField.fixedField ⊤ = ⊥
this : MulSemiringAction Gal(L/K) B := IsIntegralClosure.MulSemiringAction A K L B
b : B
hb : (algebraMap B L) b ∈ Set.range ⇑(algebraMap K L)
⊢ ∃ a, (algebraMap A B) a = b

Tactic:
obtain ⟨k, hk⟩ := hb

Goal state after:
A : Type u_1
K : Type u_2
L : Type u_3
B : Type u_4
inst✝¹⁵ : CommRing A
inst✝¹⁴ : CommRing B
inst✝¹³ : Field K
inst✝¹² : Field L
inst✝¹¹ : Algebra A K
inst✝¹⁰ : Algebra B L
inst✝⁹ : IsFractionRing A K
inst✝⁸ : IsFractionRing B L
inst✝⁷ : Algebra A B
inst✝⁶ : Algebra K L
inst✝⁵ : Algebra A L
inst✝⁴ : IsScalarTower A K L
inst✝³ : IsScalarTower A B L
inst✝² : IsIntegrallyClosed A
inst✝¹ : IsIntegralClosure B A L
inst✝ : FiniteDimensional K L
h✝ : IsGalois K L
h : IntermediateField.fixedField ⊤ = ⊥
this : MulSemiringAction Gal(L/K) B := IsIntegralClosure.MulSemiringAction A K L B
b : B
k : K
hk : (algebraMap K L) k = (algebraMap B L) b
⊢ ∃ a, (algebraMap A B) a = b
Module: Mathlib.NumberTheory.NumberField.CanonicalEmbedding.Basic

Goal state before:
pp: case fst
K : Type u_1
inst✝ : Field K
s : Set { w // w.IsReal }
A : Set (mixedSpace K)
x : mixedSpace K
hA : ∀ (x : mixedSpace K), x ∈ A ↔ (fun w ↦ ‖x.1 w‖, x.2) ∈ A
hx₁ : x ∈ A
hx₂ : ∀ (w : { w // w.IsReal }), x.1 w ≠ 0
x✝ : (∀ w ∈ s, x.1 w < 0) ∧ ∀ w ∉ s, x.1 w > 0
h₁ : ∀ w ∈ s, x.1 w < 0
h₂ : ∀ w ∉ s, x.1 w > 0
w : { w // w.IsReal }
⊢ ((negAt s) (fun w ↦ ‖x.1 w‖, x.2)).1 w = x.1 w

pp: case snd
K : Type u_1
inst✝ : Field K
s : Set { w // w.IsReal }
A : Set (mixedSpace K)
x : mixedSpace K
hA : ∀ (x : mixedSpace K), x ∈ A ↔ (fun w ↦ ‖x.1 w‖, x.2) ∈ A
hx₁ : x ∈ A
hx₂ : ∀ (w : { w // w.IsReal }), x.1 w ≠ 0
x✝ : (∀ w ∈ s, x.1 w < 0) ∧ ∀ w ∉ s, x.1 w > 0
h₁ : ∀ w ∈ s, x.1 w < 0
h₂ : ∀ w ∉ s, x.1 w > 0
w : { w // w.IsComplex }
⊢ ((negAt s) (fun w ↦ ‖x.1 w‖, x.2)).2 w = x.2 w

Tactic:
· by_cases hw : w ∈ s
    · simp [negAt_apply_isReal_and_mem _ hw, abs_of_neg (h₁ w hw)]
    · simp [negAt_apply_isReal_and_notMem _ hw, abs_of_pos (h₂ w hw)]

Goal state after:
case snd
K : Type u_1
inst✝ : Field K
s : Set { w // w.IsReal }
A : Set (mixedSpace K)
x : mixedSpace K
hA : ∀ (x : mixedSpace K), x ∈ A ↔ (fun w ↦ ‖x.1 w‖, x.2) ∈ A
hx₁ : x ∈ A
hx₂ : ∀ (w : { w // w.IsReal }), x.1 w ≠ 0
x✝ : (∀ w ∈ s, x.1 w < 0) ∧ ∀ w ∉ s, x.1 w > 0
h₁ : ∀ w ∈ s, x.1 w < 0
h₂ : ∀ w ∉ s, x.1 w > 0
w : { w // w.IsComplex }
⊢ ((negAt s) (fun w ↦ ‖x.1 w‖, x.2)).2 w = x.2 w
Module: Mathlib.NumberTheory.NumberField.CanonicalEmbedding.Basic

Goal state before:
pp: K : Type u_1
inst✝ : Field K
A : Set (mixedSpace K)
hA : ∀ (x : mixedSpace K), x ∈ A ↔ (fun w ↦ ‖x.1 w‖, x.2) ∈ A
x : mixedSpace K
⊢ (∃ i, x ∈ ⇑(negAt i) '' plusPart A) ∨ x ∈ A ∧ x ∈ ⋃ w, {x | x.1 w = 0} ↔ x ∈ A

Tactic:
Set.mem_iUnion

Goal state after:
K : Type u_1
inst✝ : Field K
A : Set (mixedSpace K)
hA : ∀ (x : mixedSpace K), x ∈ A ↔ (fun w ↦ ‖x.1 w‖, x.2) ∈ A
x : mixedSpace K
⊢ ((∃ i, x ∈ ⇑(negAt i) '' plusPart A) ∨ x ∈ A ∧ ∃ i, x ∈ {x | x.1 i = 0}) ↔ x ∈ A
Module: Mathlib.RingTheory.Invariant.Galois

Goal state before:
pp: A : Type u_1
B : Type u_2
inst✝¹⁹ : CommRing A
inst✝¹⁸ : CommRing B
inst✝¹⁷ : Algebra A B
G : Type u_3
inst✝¹⁶ : Finite G
inst✝¹⁵ : Group G
inst✝¹⁴ : MulSemiringAction G B
inst✝¹³ : Algebra.IsInvariant A B G
P : Ideal A
Q : Ideal B
inst✝¹² : Q.LiesOver P
inst✝¹¹ : P.IsPrime
inst✝¹⁰ : Q.IsPrime
K : Type u_4
L : Type u_5
inst✝⁹ : Field K
inst✝⁸ : Field L
inst✝⁷ : Algebra K L
inst✝⁶ : Algebra (A ⧸ P) K
inst✝⁵ : IsFractionRing (A ⧸ P) K
inst✝⁴ : Algebra (B ⧸ Q) L
inst✝³ : IsFractionRing (B ⧸ Q) L
inst✝² : Algebra (A ⧸ P) L
inst✝¹ : IsScalarTower (A ⧸ P) (B ⧸ Q) L
inst✝ : IsScalarTower (A ⧸ P) K L
this✝ : Algebra.IsIntegral A B
this : Algebra.IsAlgebraic K L
x y : B ⧸ Q
hy : y ∈ nonZeroDivisors (B ⧸ Q)
a : A
ha : (algebraMap A (A ⧸ P)) a ≠ 0
b : B
h : (algebraMap A (A ⧸ P)) a • x = y * (algebraMap B (B ⧸ Q)) b
val✝ : Fintype G
p : A[X]
hp : Polynomial.map (algebraMap A B) p = MulSemiringAction.charpoly G b
h_monic : p.Monic
h_eval : (aeval b) p = 0
q : A[X] := p.comp (C a * X)
d : L := (algebraMap (B ⧸ Q) L) x / (algebraMap (B ⧸ Q) L) y
⊢ (algebraMap K L).comp (algebraMap (A ⧸ P) K) = (algebraMap (B ⧸ Q) L).comp (algebraMap (A ⧸ P) (B ⧸ Q))

Tactic:
simp_rw [← IsScalarTower.algebraMap_eq]

Goal state after:
Module: Mathlib.RingTheory.Invariant.Galois

Goal state before:
pp: A : Type u_1
B : Type u_2
inst✝¹⁹ : CommRing A
inst✝¹⁸ : CommRing B
inst✝¹⁷ : Algebra A B
G : Type u_3
inst✝¹⁶ : Finite G
inst✝¹⁵ : Group G
inst✝¹⁴ : MulSemiringAction G B
inst✝¹³ : Algebra.IsInvariant A B G
P : Ideal A
Q : Ideal B
inst✝¹² : Q.LiesOver P
inst✝¹¹ : P.IsPrime
inst✝¹⁰ : Q.IsPrime
K : Type u_4
L : Type u_5
inst✝⁹ : Field K
inst✝⁸ : Field L
inst✝⁷ : Algebra K L
inst✝⁶ : Algebra (A ⧸ P) K
inst✝⁵ : IsFractionRing (A ⧸ P) K
inst✝⁴ : Algebra (B ⧸ Q) L
inst✝³ : IsFractionRing (B ⧸ Q) L
inst✝² : Algebra (A ⧸ P) L
inst✝¹ : IsScalarTower (A ⧸ P) (B ⧸ Q) L
inst✝ : IsScalarTower (A ⧸ P) K L
this✝ : Algebra.IsIntegral A B
this : Algebra.IsAlgebraic K L
x y : B ⧸ Q
hy : y ∈ nonZeroDivisors (B ⧸ Q)
a : A
ha : (algebraMap A (A ⧸ P)) a ≠ 0
b : B
h : (algebraMap A (A ⧸ P)) a • x = y * (algebraMap B (B ⧸ Q)) b
val✝ : Fintype G
p : A[X]
hp : Polynomial.map (algebraMap A B) p = MulSemiringAction.charpoly G b
h_monic : p.Monic
h_eval : (aeval b) p = 0
q : A[X] := p.comp (C a * X)
d : L := (algebraMap (B ⧸ Q) L) x / (algebraMap (B ⧸ Q) L) y
comm₁ : (algebraMap K L).comp (algebraMap (A ⧸ P) K) = (algebraMap (B ⧸ Q) L).comp (algebraMap (A ⧸ P) (B ⧸ Q))
⊢ (algebraMap (A ⧸ P) (B ⧸ Q)).comp (algebraMap A (A ⧸ P)) = (algebraMap B (B ⧸ Q)).comp (algebraMap A B)

Tactic:
simp_rw [← IsScalarTower.algebraMap_eq]

Goal state after:
Module: Mathlib.RingTheory.IntegralClosure.IntegralRestrict

Goal state before:
pp: case neg
A : Type u_1
B : Type u_6
inst✝⁸ : CommRing A
inst✝⁷ : CommRing B
inst✝⁶ : Algebra A B
inst✝⁵ : IsDomain A
inst✝⁴ : IsIntegrallyClosed A
inst✝³ : IsDomain B
inst✝² : IsIntegrallyClosed B
inst✝¹ : Module.Finite A B
inst✝ : IsTorsionFree A B
x : B
this : FiniteDimensional (FractionRing A) (FractionRing B)
hx : ¬x = 0
K : Type u_1 := FractionRing A
L : Type u_6 := FractionRing B
E : Type u_6 := AlgebraicClosure L
⊢ x ∣ (algebraMap A B) ((intNorm A B) x)

Tactic:
suffices IsIntegral A ((algebraMap B L x)⁻¹ * (algebraMap A L (intNorm A B x))) by
    obtain ⟨y, hy⟩ := IsIntegrallyClosed.isIntegral_iff.mp <|
      _root_.IsIntegral.tower_top (A := B) this
    refine ⟨y, ?_⟩
    apply FaithfulSMul.algebraMap_injective B L
    rw [← algebraMap_apply, map_mul, hy, mul_inv_cancel_left₀]
    exact (map_ne_zero_iff _ (FaithfulSMul.algebraMap_injective B L)).mpr hx

Goal state after:
case neg
A : Type u_1
B : Type u_6
inst✝⁸ : CommRing A
inst✝⁷ : CommRing B
inst✝⁶ : Algebra A B
inst✝⁵ : IsDomain A
inst✝⁴ : IsIntegrallyClosed A
inst✝³ : IsDomain B
inst✝² : IsIntegrallyClosed B
inst✝¹ : Module.Finite A B
inst✝ : IsTorsionFree A B
x : B
this : FiniteDimensional (FractionRing A) (FractionRing B)
hx : ¬x = 0
K : Type u_1 := FractionRing A
L : Type u_6 := FractionRing B
E : Type u_6 := AlgebraicClosure L
⊢ IsIntegral A (((algebraMap B L) x)⁻¹ * (algebraMap A L) ((intNorm A B) x))
Module: Mathlib.NumberTheory.NumberField.Discriminant.Basic

Goal state before:
pp: A : Type u_2
inst✝¹ : Field A
inst✝ : CharZero A
N : ℕ
D : ℕ := rankOfDiscrBdd N
B : ℝ≥0 := boundOfDiscBdd N
C : ℕ := ⌈max B 1 ^ D * ↑(D.choose (D / 2))⌉₊
x✝¹ : { F // FiniteDimensional ℚ ↥F }
K : IntermediateField ℚ A
hK₀ : FiniteDimensional ℚ ↥K
x✝ : ⟨K, hK₀⟩ ∈ {K | {w | w.IsReal}.Nonempty ∧ |discr ↥↑K| ≤ ↑N}
hK₁ : {w | w.IsReal}.Nonempty
hK₂ : |discr ↥↑⟨K, hK₀⟩| ≤ ↑N
⊢ ∃
    x ∈
      ⋃ f,
        ⋃ (_ : f.natDegree ≤ D ∧ ∀ (i : ℕ), f.coeff i ∈ Set.Icc (-↑C) ↑C),
          ↑(Polynomial.map (algebraMap ℤ A) f).roots.toFinset,
    K = ℚ⟮x⟯

Tactic:
Set.mem_iUnion

Goal state after:
A : Type u_2
inst✝¹ : Field A
inst✝ : CharZero A
N : ℕ
D : ℕ := rankOfDiscrBdd N
B : ℝ≥0 := boundOfDiscBdd N
C : ℕ := ⌈max B 1 ^ D * ↑(D.choose (D / 2))⌉₊
x✝¹ : { F // FiniteDimensional ℚ ↥F }
K : IntermediateField ℚ A
hK₀ : FiniteDimensional ℚ ↥K
x✝ : ⟨K, hK₀⟩ ∈ {K | {w | w.IsReal}.Nonempty ∧ |discr ↥↑K| ≤ ↑N}
hK₁ : {w | w.IsReal}.Nonempty
hK₂ : |discr ↥↑⟨K, hK₀⟩| ≤ ↑N
⊢ ∃ x,
    (∃ i,
        ∃ (_ : i.natDegree ≤ D ∧ ∀ (i_1 : ℕ), i.coeff i_1 ∈ Set.Icc (-↑C) ↑C),
          x ∈ ↑(Polynomial.map (algebraMap ℤ A) i).roots.toFinset) ∧
      K = ℚ⟮x⟯
Module: Mathlib.NumberTheory.RamificationInertia.Unramified

Goal state before:
pp: R : Type u_1
S : Type u_2
inst✝⁷ : CommRing R
inst✝⁶ : CommRing S
inst✝⁵ : Algebra R S
inst✝⁴ : IsDomain R
inst✝³ : IsDomain S
inst✝² : Module.IsTorsionFree R S
inst✝¹ : CharZero R
inst✝ : Algebra.IsIntegral R S
this✝² : IsFractionRing S (Localization.AtPrime ⊥)
this✝¹ : Field (Localization.AtPrime ⊥) := IsFractionRing.toField S
this✝ : FaithfulSMul R (Localization.AtPrime ⊥)
this : Algebra (FractionRing R) (Localization.AtPrime ⊥) := FractionRing.liftAlgebra R (Localization.AtPrime ⊥)
⊢ IsUnramifiedAt R ⊥

Tactic:
have : Algebra.IsAlgebraic (FractionRing R) (Localization.AtPrime ⊥) :=
    isAlgebraic_of_isFractionRing R S (FractionRing R) (Localization.AtPrime (⊥ : Ideal S))

Goal state after:
R : Type u_1
S : Type u_2
inst✝⁷ : CommRing R
inst✝⁶ : CommRing S
inst✝⁵ : Algebra R S
inst✝⁴ : IsDomain R
inst✝³ : IsDomain S
inst✝² : Module.IsTorsionFree R S
inst✝¹ : CharZero R
inst✝ : Algebra.IsIntegral R S
this✝³ : IsFractionRing S (Localization.AtPrime ⊥)
this✝² : Field (Localization.AtPrime ⊥) := IsFractionRing.toField S
this✝¹ : FaithfulSMul R (Localization.AtPrime ⊥)
this✝ : Algebra (FractionRing R) (Localization.AtPrime ⊥) := FractionRing.liftAlgebra R (Localization.AtPrime ⊥)
this : Algebra.IsAlgebraic (FractionRing R) (Localization.AtPrime ⊥)
⊢ IsUnramifiedAt R ⊥
Module: Mathlib.NumberTheory.NumberField.Discriminant.Basic

Goal state before:
pp: A : Type u_2
inst✝¹ : Field A
inst✝ : CharZero A
N : ℕ
D : ℕ := rankOfDiscrBdd N
B : ℝ≥0 := boundOfDiscBdd N
C : ℕ := ⌈max (sqrt (1 + B ^ 2)) 1 ^ D * ↑(D.choose (D / 2))⌉₊
x✝¹ : { F // FiniteDimensional ℚ ↥F }
K : IntermediateField ℚ A
hK₀ : FiniteDimensional ℚ ↥K
x✝ : ⟨K, hK₀⟩ ∈ {K | {w | w.IsComplex}.Nonempty ∧ |discr ↥↑K| ≤ ↑N}
hK₁ : {w | w.IsComplex}.Nonempty
hK₂ : |discr ↥↑⟨K, hK₀⟩| ≤ ↑N
⊢ ∃
    x ∈
      ⋃ f,
        ⋃ (_ : f.natDegree ≤ D ∧ ∀ (i : ℕ), f.coeff i ∈ Set.Icc (-↑C) ↑C),
          ↑(Polynomial.map (algebraMap ℤ A) f).roots.toFinset,
    K = ℚ⟮x⟯

Tactic:
Set.mem_iUnion

Goal state after:
A : Type u_2
inst✝¹ : Field A
inst✝ : CharZero A
N : ℕ
D : ℕ := rankOfDiscrBdd N
B : ℝ≥0 := boundOfDiscBdd N
C : ℕ := ⌈max (sqrt (1 + B ^ 2)) 1 ^ D * ↑(D.choose (D / 2))⌉₊
x✝¹ : { F // FiniteDimensional ℚ ↥F }
K : IntermediateField ℚ A
hK₀ : FiniteDimensional ℚ ↥K
x✝ : ⟨K, hK₀⟩ ∈ {K | {w | w.IsComplex}.Nonempty ∧ |discr ↥↑K| ≤ ↑N}
hK₁ : {w | w.IsComplex}.Nonempty
hK₂ : |discr ↥↑⟨K, hK₀⟩| ≤ ↑N
⊢ ∃ x,
    (∃ i,
        ∃ (_ : i.natDegree ≤ D ∧ ∀ (i_1 : ℕ), i.coeff i_1 ∈ Set.Icc (-↑C) ↑C),
          x ∈ ↑(Polynomial.map (algebraMap ℤ A) i).roots.toFinset) ∧
      K = ℚ⟮x⟯
Module: Mathlib.NumberTheory.NumberField.ClassNumber

Goal state before:
pp: case neg
K : Type u_1
inst✝² : Field K
inst✝¹ : NumberField K
inst✝ : IsGalois ℚ K
h✝ :
  ∀ p ∈ Finset.Icc 1 ⌊(4 / π) ^ nrComplexPlaces K * (↑(finrank ℚ K)! / ↑(finrank ℚ K) ^ finrank ℚ K * √|↑(discr K)|)⌋₊,
    Nat.Prime p →
      ∃ P ∈ (span {↑p}).primesOver (𝓞 K),
        ⌊(4 / π) ^ nrComplexPlaces K * (↑(finrank ℚ K)! / ↑(finrank ℚ K) ^ finrank ℚ K * √|↑(discr K)|)⌋₊ <
            p ^ P.inertiaDeg ℤ ∨
          Submodule.IsPrincipal P
p : ℕ
hpmem :
  p ∈ Finset.Icc 1 ⌊(4 / π) ^ nrComplexPlaces K * (↑(finrank ℚ K)! / ↑(finrank ℚ K) ^ finrank ℚ K * √|↑(discr K)|)⌋₊
hp : Nat.Prime p
P : Ideal (𝓞 K)
x✝ : P ∈ (span {↑p}).primesOver (𝓞 K)
hple :
  p ^ P.inertiaDeg ℤ ≤ ⌊(4 / π) ^ nrComplexPlaces K * (↑(finrank ℚ K)! / ↑(finrank ℚ K) ^ finrank ℚ K * √|↑(discr K)|)⌋₊
hP1 : P.IsPrime
hP2 : P.LiesOver (span {↑p})
Q : Ideal (𝓞 K)
H :
  ⌊(4 / π) ^ nrComplexPlaces K * (↑(finrank ℚ K)! / ↑(finrank ℚ K) ^ finrank ℚ K * √|↑(discr K)|)⌋₊ <
      p ^ Q.inertiaDeg ℤ ∨
    Submodule.IsPrincipal Q
hQ1 : Q.IsPrime
hQ2 : Q.LiesOver (span {↑p})
this : (span {↑p}).IsMaximal
h :
  ¬⌊(4 / π) ^ nrComplexPlaces K * (↑(finrank ℚ K)! / ↑(finrank ℚ K) ^ finrank ℚ K * √|↑(discr K)|)⌋₊ <
      p ^ P.inertiaDeg ℤ
⊢ Submodule.IsPrincipal P

Tactic:
rw [inertiaDeg_eq_of_isGaloisGroup (span {↑p}) Q P (K ≃ₐ[ℚ] K)] at H

Goal state after:
case neg
K : Type u_1
inst✝² : Field K
inst✝¹ : NumberField K
inst✝ : IsGalois ℚ K
h✝ :
  ∀ p ∈ Finset.Icc 1 ⌊(4 / π) ^ nrComplexPlaces K * (↑(finrank ℚ K)! / ↑(finrank ℚ K) ^ finrank ℚ K * √|↑(discr K)|)⌋₊,
    Nat.Prime p →
      ∃ P ∈ (span {↑p}).primesOver (𝓞 K),
        ⌊(4 / π) ^ nrComplexPlaces K * (↑(finrank ℚ K)! / ↑(finrank ℚ K) ^ finrank ℚ K * √|↑(discr K)|)⌋₊ <
            p ^ P.inertiaDeg ℤ ∨
          Submodule.IsPrincipal P
p : ℕ
hpmem :
  p ∈ Finset.Icc 1 ⌊(4 / π) ^ nrComplexPlaces K * (↑(finrank ℚ K)! / ↑(finrank ℚ K) ^ finrank ℚ K * √|↑(discr K)|)⌋₊
hp : Nat.Prime p
P : Ideal (𝓞 K)
x✝ : P ∈ (span {↑p}).primesOver (𝓞 K)
hple :
  p ^ P.inertiaDeg ℤ ≤ ⌊(4 / π) ^ nrComplexPlaces K * (↑(finrank ℚ K)! / ↑(finrank ℚ K) ^ finrank ℚ K * √|↑(discr K)|)⌋₊
hP1 : P.IsPrime
hP2 : P.LiesOver (span {↑p})
Q : Ideal (𝓞 K)
H :
  ⌊(4 / π) ^ nrComplexPlaces K * (↑(finrank ℚ K)! / ↑(finrank ℚ K) ^ finrank ℚ K * √|↑(discr K)|)⌋₊ <
      p ^ P.inertiaDeg ℤ ∨
    Submodule.IsPrincipal Q
hQ1 : Q.IsPrime
hQ2 : Q.LiesOver (span {↑p})
this : (span {↑p}).IsMaximal
h :
  ¬⌊(4 / π) ^ nrComplexPlaces K * (↑(finrank ℚ K)! / ↑(finrank ℚ K) ^ finrank ℚ K * √|↑(discr K)|)⌋₊ <
      p ^ P.inertiaDeg ℤ
⊢ Submodule.IsPrincipal P
Module: Mathlib.RingTheory.LocalRing.Quotient

Goal state before:
pp: R : Type u_1
S : Type u_2
inst✝⁴ : CommRing R
inst✝³ : CommRing S
inst✝² : Algebra R S
inst✝¹ : IsLocalRing R
inst✝ : Module.Finite R S
s : Set S
⊢ span (R ⧸ p) (⇑(Ideal.Quotient.mk pS) '' s) = ⊤ ↔ span R s = ⊤

Tactic:
by
  have H : (span (R ⧸ p) ((Ideal.Quotient.mk (I := pS)) '' s)).restrictScalars R =
      (span R s).map (IsScalarTower.toAlgHom R S (S ⧸ pS) : S →ₗ[R] S ⧸ pS) := by
    rw [map_span, ← restrictScalars_span R (R ⧸ p) Ideal.Quotient.mk_surjective,
      LinearMap.coe_coe, IsScalarTower.coe_toAlgHom', Ideal.Quotient.algebraMap_eq]
  constructor
  · intro hs
    rw [← top_le_iff]
    apply le_of_le_smul_of_le_jacobson_bot
    · exact Module.finite_def.mp ‹_›
    · exact (jacobson_eq_maximalIdeal ⊥ bot_ne_top).ge
    · rw [Ideal.smul_top_eq_map]
      rintro x -
      have : LinearMap.ker (IsScalarTower.toAlgHom R S (S ⧸ pS) : S →ₗ[R] S ⧸ pS) =
          Submodule.restrictScalars R pS := by
        ext; simp [Ideal.Quotient.eq_zero_iff_mem]
      rw [← this, ← comap_map_eq, mem_comap, ← H, hs, restrictScalars_top]
      exact mem_top
  · intro hs
    rwa [hs, Submodule.map_top, LinearMap.range_eq_top.mpr,
      restrictScalars_eq_top_iff] at H
    rw [LinearMap.coe_coe, IsScalarTower.coe_toAlgHom', Ideal.Quotient.algebraMap_eq]
    exact Ideal.Quotient.mk_surjective

Goal state after:
Module: Mathlib.RingTheory.DedekindDomain.PID

Goal state before:
pp: R : Type u_1
inst✝³ : CommRing R
A : Type u_2
inst✝² : CommRing A
inst✝¹ : Algebra R A
S : Submonoid R
inst✝ : IsLocalization S A
hS : S ≤ R⁰
hf : {I | I.IsMaximal}.Finite
I I' : FractionalIdeal S A
hinv : ↑I * ↑I' = ↑1
hinv' : I * I' = 1
s : Finset (Ideal R) := hf.toFinset
this✝ : DecidableEq (Ideal R)
coprime : ∀ M ∈ s, ∀ M' ∈ s.erase M, M ⊔ M' = ⊤
nle : ∀ M ∈ s, ¬⨅ M' ∈ s.erase M, M' ≤ M
a : Ideal R → A
ha : ∀ M ∈ s, a M ∈ I
b : Ideal R → A
hb : ∀ M ∈ s, b M ∈ I'
hm : ∀ M ∈ s, a M * b M ∉ IsLocalization.coeSubmodule A M
u : Ideal R → R
hu : ∀ M ∈ s, u M ∈ ⨅ M' ∈ s.erase M, M'
hum : ∀ M ∈ s, u M ∉ M
v : A := ∑ M ∈ s, u M • b M
hv : v ∈ I'
h : ¬Submodule.comap (Algebra.linearMap R A) (↑↑(Units.mkOfMulEqOne I I' hinv') * (R ∙ v)) = ⊤
M : Ideal R
hJM : Submodule.comap (Algebra.linearMap R A) (↑↑(Units.mkOfMulEqOne I I' hinv') * (R ∙ v)) ≤ M
hM : M ∈ hf.toFinset
this : ∀ a ∈ I, ∀ b ∈ I', ∃ c, (algebraMap R A) c = a * b
hmem : a M * v ∈ IsLocalization.coeSubmodule A M
⊢ False

Tactic:
simp_rw [v, Finset.mul_sum, mul_smul_comm] at hmem

Goal state after:
R : Type u_1
inst✝³ : CommRing R
A : Type u_2
inst✝² : CommRing A
inst✝¹ : Algebra R A
S : Submonoid R
inst✝ : IsLocalization S A
hS : S ≤ R⁰
hf : {I | I.IsMaximal}.Finite
I I' : FractionalIdeal S A
hinv : ↑I * ↑I' = ↑1
hinv' : I * I' = 1
s : Finset (Ideal R) := hf.toFinset
this✝ : DecidableEq (Ideal R)
coprime : ∀ M ∈ s, ∀ M' ∈ s.erase M, M ⊔ M' = ⊤
nle : ∀ M ∈ s, ¬⨅ M' ∈ s.erase M, M' ≤ M
a : Ideal R → A
ha : ∀ M ∈ s, a M ∈ I
b : Ideal R → A
hb : ∀ M ∈ s, b M ∈ I'
hm : ∀ M ∈ s, a M * b M ∉ IsLocalization.coeSubmodule A M
u : Ideal R → R
hu : ∀ M ∈ s, u M ∈ ⨅ M' ∈ s.erase M, M'
hum : ∀ M ∈ s, u M ∉ M
v : A := ∑ M ∈ s, u M • b M
hv : v ∈ I'
h : ¬Submodule.comap (Algebra.linearMap R A) (↑↑(Units.mkOfMulEqOne I I' hinv') * (R ∙ v)) = ⊤
M : Ideal R
hJM : Submodule.comap (Algebra.linearMap R A) (↑↑(Units.mkOfMulEqOne I I' hinv') * (R ∙ v)) ≤ M
hM : M ∈ hf.toFinset
this : ∀ a ∈ I, ∀ b ∈ I', ∃ c, (algebraMap R A) c = a * b
hmem : ∑ x ∈ s, u x • (a M * b x) ∈ IsLocalization.coeSubmodule A M
⊢ False
Module: Mathlib.RingTheory.DedekindDomain.PID

Goal state before:
pp: R : Type u_1
inst✝¹³ : CommRing R
inst✝¹² : IsDedekindDomain R
S : Type u_2
inst✝¹¹ : CommRing S
inst✝¹⁰ : Algebra R S
inst✝⁹ : Module.IsTorsionFree R S
inst✝⁸ : Module.Finite R S
p : Ideal R
hp0 : p ≠ ⊥
inst✝⁷ : p.IsPrime
Sₚ : Type u_3
inst✝⁶ : CommRing Sₚ
inst✝⁵ : Algebra S Sₚ
inst✝⁴ : IsLocalization (Algebra.algebraMapSubmonoid S p.primeCompl) Sₚ
inst✝³ : Algebra R Sₚ
inst✝² : IsScalarTower R S Sₚ
inst✝¹ : IsDedekindDomain Sₚ
inst✝ : IsDomain S
P : Ideal Sₚ
hP : P.IsPrime
hP0 : P ≠ ⊥
non_zero_div : Algebra.algebraMapSubmonoid S p.primeCompl ≤ S⁰
this✝¹ : Algebra (Localization.AtPrime p) Sₚ := localizationAlgebra p.primeCompl S
this✝ : IsScalarTower R (Localization.AtPrime p) Sₚ
pid : IsPrincipalIdealRing (Localization.AtPrime p)
p' : Ideal (Localization.AtPrime p)
hpu : ∀ (y : Ideal (Localization.AtPrime p)), (fun P ↦ P ≠ ⊥ ∧ P.IsPrime) y → y = p'
hp'0 : p' ≠ ⊥
hp'p : p'.IsPrime
this : IsLocalRing.maximalIdeal (Localization.AtPrime p) ≠ ⊥
⊢ {P} ≤ normalizedFactors (Ideal.map (algebraMap R Sₚ) p)

Tactic:
← normalize_eq P,

Goal state after:
R : Type u_1
inst✝¹³ : CommRing R
inst✝¹² : IsDedekindDomain R
S : Type u_2
inst✝¹¹ : CommRing S
inst✝¹⁰ : Algebra R S
inst✝⁹ : Module.IsTorsionFree R S
inst✝⁸ : Module.Finite R S
p : Ideal R
hp0 : p ≠ ⊥
inst✝⁷ : p.IsPrime
Sₚ : Type u_3
inst✝⁶ : CommRing Sₚ
inst✝⁵ : Algebra S Sₚ
inst✝⁴ : IsLocalization (Algebra.algebraMapSubmonoid S p.primeCompl) Sₚ
inst✝³ : Algebra R Sₚ
inst✝² : IsScalarTower R S Sₚ
inst✝¹ : IsDedekindDomain Sₚ
inst✝ : IsDomain S
P : Ideal Sₚ
hP : P.IsPrime
hP0 : P ≠ ⊥
non_zero_div : Algebra.algebraMapSubmonoid S p.primeCompl ≤ S⁰
this✝¹ : Algebra (Localization.AtPrime p) Sₚ := localizationAlgebra p.primeCompl S
this✝ : IsScalarTower R (Localization.AtPrime p) Sₚ
pid : IsPrincipalIdealRing (Localization.AtPrime p)
p' : Ideal (Localization.AtPrime p)
hpu : ∀ (y : Ideal (Localization.AtPrime p)), (fun P ↦ P ≠ ⊥ ∧ P.IsPrime) y → y = p'
hp'0 : p' ≠ ⊥
hp'p : p'.IsPrime
this : IsLocalRing.maximalIdeal (Localization.AtPrime p) ≠ ⊥
⊢ {normalize P} ≤ normalizedFactors (Ideal.map (algebraMap R Sₚ) p)
Module: Mathlib.RingTheory.Ideal.Norm.RelNorm

Goal state before:
pp: R : Type u_1
inst✝⁸ : CommRing R
inst✝⁷ : IsDomain R
S : Type u_3
inst✝⁶ : CommRing S
inst✝⁵ : IsDomain S
inst✝⁴ : IsIntegrallyClosed R
inst✝³ : IsIntegrallyClosed S
inst✝² : Algebra R S
inst✝¹ : Module.Finite R S
inst✝ : IsTorsionFree R S
x : R
hx : x ∈ ⇑(Algebra.intNorm R S) '' ↑⊥
⊢ x = 0

Tactic:
simpa using hx

Goal state after:
Module: Mathlib.RingTheory.Ideal.Norm.RelNorm

Goal state before:
pp: R : Type u_1
inst✝⁹ : CommRing R
inst✝⁸ : IsDomain R
S : Type u_3
inst✝⁷ : CommRing S
inst✝⁶ : IsDomain S
inst✝⁵ : IsIntegrallyClosed R
inst✝⁴ : IsIntegrallyClosed S
inst✝³ : Algebra R S
inst✝² : Module.Finite R S
inst✝¹ : IsTorsionFree R S
inst✝ : Free R S
I : Ideal S
x : S
hx : x ∈ I
⊢ (Algebra.norm R) x ∈ spanNorm R I

Tactic:
refine subset_span ⟨x, hx, ?_⟩

Goal state after:
R : Type u_1
inst✝⁹ : CommRing R
inst✝⁸ : IsDomain R
S : Type u_3
inst✝⁷ : CommRing S
inst✝⁶ : IsDomain S
inst✝⁵ : IsIntegrallyClosed R
inst✝⁴ : IsIntegrallyClosed S
inst✝³ : Algebra R S
inst✝² : Module.Finite R S
inst✝¹ : IsTorsionFree R S
inst✝ : Free R S
I : Ideal S
x : S
hx : x ∈ I
⊢ (Algebra.intNorm R S) x = (Algebra.norm R) x
Module: Mathlib.NumberTheory.NumberField.Discriminant.Different

Goal state before:
pp: L : Type u_3
inst✝² : Field L
inst✝¹ : NumberField L
K₁ K₂ : IntermediateField ℚ L
inst✝ : IsGalois ℚ ↥K₁
h : IsCoprime (discr ↥K₁) (discr ↥K₂)
this✝ : K₁ ⊓ K₂ ≠ ⊥
this : 1 < finrank ℚ ↥(K₁ ⊓ K₂)
⊢ ¬|discr ↥(K₁ ⊓ K₂)| = 1

Tactic:
linarith [abs_discr_gt_two this]

Goal state after:
Module: Mathlib.RingTheory.Ideal.Norm.RelNorm

Goal state before:
pp: case inr.inl
R : Type u_1
inst✝⁸ : CommRing R
inst✝⁷ : IsDomain R
S : Type u_3
inst✝⁶ : CommRing S
inst✝⁵ : IsDomain S
inst✝⁴ : IsIntegrallyClosed R
inst✝³ : IsIntegrallyClosed S
inst✝² : Algebra R S
inst✝¹ : Module.Finite R S
inst✝ : IsTorsionFree R S
eq_bot_or_top : ∀ (I : Ideal R), I = ⊥ ∨ I = ⊤
I J : Ideal S
hI : spanNorm R I = ⊤
hJ : spanNorm R J = ⊥
⊢ spanNorm R (I * J) ≤ ⊥

Tactic:
spanNorm_eq_bot_iff.mp hJ,

Goal state after:
case inr.inl
R : Type u_1
inst✝⁸ : CommRing R
inst✝⁷ : IsDomain R
S : Type u_3
inst✝⁶ : CommRing S
inst✝⁵ : IsDomain S
inst✝⁴ : IsIntegrallyClosed R
inst✝³ : IsIntegrallyClosed S
inst✝² : Algebra R S
inst✝¹ : Module.Finite R S
inst✝ : IsTorsionFree R S
eq_bot_or_top : ∀ (I : Ideal R), I = ⊥ ∨ I = ⊤
I J : Ideal S
hI : spanNorm R I = ⊤
hJ : spanNorm R J = ⊥
⊢ spanNorm R (I * ⊥) ≤ ⊥
Module: Mathlib.RingTheory.Prime

Goal state before:
pp: R : Type u_1
inst✝¹ : CommMonoidWithZero R
inst✝ : IsCancelMulZero R
p : R
n : ℕ
hp : Prime p
t u : Finset ℕ
b c : R
htus : t ∪ u = range n
htu : Disjoint t u
hx : (b * ∏ i ∈ t, p) * (c * ∏ i ∈ u, p) = b * c * p ^ n
⊢ #t + #u = n

Tactic:
← card_union_of_disjoint htu,

Goal state after:
R : Type u_1
inst✝¹ : CommMonoidWithZero R
inst✝ : IsCancelMulZero R
p : R
n : ℕ
hp : Prime p
t u : Finset ℕ
b c : R
htus : t ∪ u = range n
htu : Disjoint t u
hx : (b * ∏ i ∈ t, p) * (c * ∏ i ∈ u, p) = b * c * p ^ n
⊢ #(t ∪ u) = n
Module: Mathlib.NumberTheory.NumberField.Cyclotomic.Basic

Goal state before:
pp: case refine_1
p k : ℕ
hp : Fact (Nat.Prime p)
hζ : IsPrimitiveRoot (zeta (p ^ k) ℚ (CyclotomicField (p ^ k) ℚ)) (p ^ k)
x : CyclotomicField (p ^ k) ℚ
h : IsIntegral ℤ x
⊢ x ∈ adjoin ℤ {b | b ^ p ^ k = 1}

pp: case refine_2
p k : ℕ
hp : Fact (Nat.Prime p)
hζ : IsPrimitiveRoot (zeta (p ^ k) ℚ (CyclotomicField (p ^ k) ℚ)) (p ^ k)
x : CyclotomicField (p ^ k) ℚ
⊢ (∃ y, (algebraMap (CyclotomicRing (p ^ k) ℤ ℚ) (CyclotomicField (p ^ k) ℚ)) y = x) → IsIntegral ℤ x

Tactic:
· obtain ⟨y, rfl⟩ := (isIntegralClosure_adjoin_singleton_of_prime_pow hζ).isIntegral_iff.1 h
    refine adjoin_mono ?_ y.2
    simp only [Set.singleton_subset_iff, Set.mem_ofPred_eq]
    exact hζ.pow_eq_one

Goal state after:
case refine_2
p k : ℕ
hp : Fact (Nat.Prime p)
hζ : IsPrimitiveRoot (zeta (p ^ k) ℚ (CyclotomicField (p ^ k) ℚ)) (p ^ k)
x : CyclotomicField (p ^ k) ℚ
⊢ (∃ y, (algebraMap (CyclotomicRing (p ^ k) ℤ ℚ) (CyclotomicField (p ^ k) ℚ)) y = x) → IsIntegral ℤ x
Module: Mathlib.NumberTheory.NumberField.Cyclotomic.Basic

Goal state before:
pp: K : Type u
inst✝¹ : Field K
ζ : K
inst✝ : NumberField K
k : ℕ
hk : 1 < k
hζ : IsPrimitiveRoot ζ k
⊢ Finite (𝓞 K ⧸ Ideal.span {hζ.toInteger - 1})

Tactic:
refine Ideal.finiteQuotientOfFreeOfNeBot _ (fun h ↦ ?_)

Goal state after:
K : Type u
inst✝¹ : Field K
ζ : K
inst✝ : NumberField K
k : ℕ
hk : 1 < k
hζ : IsPrimitiveRoot ζ k
h : Ideal.span {hζ.toInteger - 1} = ⊥
⊢ False