mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.NumberTheory.RamificationInertia.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
inst✝¹⁶ : FaithfulSMul A B
p : Ideal A
P : Ideal B
inst✝¹⁵ : P.IsPrime
inst✝¹⁴ : P.LiesOver p
G : Type u_3
inst✝¹³ : Group G
inst✝¹² : Finite G
inst✝¹¹ : MulSemiringAction G B
inst✝¹⁰ : IsGaloisGroup G A B
C : Type u_4
inst✝⁹ : CommRing C
inst✝⁸ : IsDomain C
inst✝⁷ : Algebra A C
inst✝⁶ : Algebra B C
inst✝⁵ : FaithfulSMul B C
inst✝⁴ : IsScalarTower A B C
GAC : Type u_5
inst✝³ : Group GAC
inst✝² : Finite GAC
inst✝¹ : MulSemiringAction GAC C
inst✝ : IsGaloisGroup GAC A C
this✝¹ : Algebra.IsIntegral A C
this✝ : Algebra.IsIntegral B C
f : GAC →* G := restrictHom GAC G A B C
H : Subgroup GAC := Subgroup.comap f (stabilizer G P)
key : ∀ (Q Q' : Ideal C) [Q.LiesOver P] [Q'.LiesOver P] (g : GAC), g • Q = Q' → g ∈ H
Q : Ideal C
left✝ : Q.IsPrime
right✝ : Q.LiesOver P
this : Q.LiesOver p
orbit_eq : orbit (↥H) Q = P.primesOver C
stabilizer_eq : stabilizer (↥H) Q = (stabilizer GAC Q).subgroupOf H
⊢ (stabilizer G P).index * (stabilizer GAC Q).relIndex H = (orbit GAC Q).ncard

Tactic:
← index_stabilizer,

Goal state after:
A : Type u_1
B : Type u_2
inst✝¹⁹ : CommRing A
inst✝¹⁸ : CommRing B
inst✝¹⁷ : Algebra A B
inst✝¹⁶ : FaithfulSMul A B
p : Ideal A
P : Ideal B
inst✝¹⁵ : P.IsPrime
inst✝¹⁴ : P.LiesOver p
G : Type u_3
inst✝¹³ : Group G
inst✝¹² : Finite G
inst✝¹¹ : MulSemiringAction G B
inst✝¹⁰ : IsGaloisGroup G A B
C : Type u_4
inst✝⁹ : CommRing C
inst✝⁸ : IsDomain C
inst✝⁷ : Algebra A C
inst✝⁶ : Algebra B C
inst✝⁵ : FaithfulSMul B C
inst✝⁴ : IsScalarTower A B C
GAC : Type u_5
inst✝³ : Group GAC
inst✝² : Finite GAC
inst✝¹ : MulSemiringAction GAC C
inst✝ : IsGaloisGroup GAC A C
this✝¹ : Algebra.IsIntegral A C
this✝ : Algebra.IsIntegral B C
f : GAC →* G := restrictHom GAC G A B C
H : Subgroup GAC := Subgroup.comap f (stabilizer G P)
key : ∀ (Q Q' : Ideal C) [Q.LiesOver P] [Q'.LiesOver P] (g : GAC), g • Q = Q' → g ∈ H
Q : Ideal C
left✝ : Q.IsPrime
right✝ : Q.LiesOver P
this : Q.LiesOver p
orbit_eq : orbit (↥H) Q = P.primesOver C
stabilizer_eq : stabilizer (↥H) Q = (stabilizer GAC Q).subgroupOf H
⊢ (stabilizer G P).index * (stabilizer GAC Q).relIndex H = (stabilizer GAC Q).index
Module: Mathlib.NumberTheory.NumberField.ClassNumber

Goal state before:
pp: K : Type u_1
inst✝¹ : Field K
inst✝ : NumberField K
C : ClassGroup (𝓞 K)
J : ↥(Ideal (𝓞 K))⁰
hJ : ClassGroup.mk0 J = C⁻¹
a : 𝓞 K
ha : a ∈ ↑↑J
h_nz : (Algebra.linearMap (𝓞 K) K) a ≠ 0
h_nm :
  ↑|(Algebra.norm ℚ) ((Algebra.linearMap (𝓞 K) K) a)| ≤
    ↑(FractionalIdeal.absNorm ↑((FractionalIdeal.mk0 K) J)) * (4 / π) ^ nrComplexPlaces K * ↑(finrank ℚ K)! /
        ↑(finrank ℚ K) ^ finrank ℚ K *
      √|↑(discr K)|
I₀ : Ideal (𝓞 K)
hI : span {a} = ↑J * I₀
this✝ : I₀ ≠ 0
I : ↥(Ideal (𝓞 K))⁰ := ⟨I₀, ⋯⟩
this : ClassGroup.mk0 I = (ClassGroup.mk0 J)⁻¹
⊢ ClassGroup.mk0 I = C

Tactic:
by

Goal state after:
Module: Mathlib.NumberTheory.RamificationInertia.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
inst✝¹⁶ : FaithfulSMul A B
p : Ideal A
P : Ideal B
inst✝¹⁵ : P.IsPrime
inst✝¹⁴ : P.LiesOver p
G : Type u_3
inst✝¹³ : Group G
inst✝¹² : Finite G
inst✝¹¹ : MulSemiringAction G B
inst✝¹⁰ : IsGaloisGroup G A B
C : Type u_4
inst✝⁹ : CommRing C
inst✝⁸ : IsDomain C
inst✝⁷ : Algebra A C
inst✝⁶ : Algebra B C
inst✝⁵ : FaithfulSMul B C
inst✝⁴ : IsScalarTower A B C
GAC : Type u_5
inst✝³ : Group GAC
inst✝² : Finite GAC
inst✝¹ : MulSemiringAction GAC C
inst✝ : IsGaloisGroup GAC A C
⊢ (p.primesOver B).ncard * (P.primesOver C).ncard = (p.primesOver C).ncard

Tactic:
by

Goal state after:
Module: Mathlib.NumberTheory.NumberField.ClassNumber

Goal state before:
pp: K : Type u_1
inst✝¹ : Field K
inst✝ : NumberField K
C : ClassGroup (𝓞 K)
J : ↥(Ideal (𝓞 K))⁰
hJ : ClassGroup.mk0 J = C⁻¹
a : 𝓞 K
ha : a ∈ ↑↑J
h_nz : (Algebra.linearMap (𝓞 K) K) a ≠ 0
h_nm :
  ↑|(Algebra.norm ℚ) ((Algebra.linearMap (𝓞 K) K) a)| ≤
    ↑(FractionalIdeal.absNorm ↑((FractionalIdeal.mk0 K) J)) * (4 / π) ^ nrComplexPlaces K * ↑(finrank ℚ K)! /
        ↑(finrank ℚ K) ^ finrank ℚ K *
      √|↑(discr K)|
I₀ : Ideal (𝓞 K)
hI : span {a} = ↑J * I₀
this : I₀ ≠ 0
I : ↥(Ideal (𝓞 K))⁰ := ⟨I₀, ⋯⟩
⊢ ↑I * ↑J = span {a}

Tactic:
by

Goal state after:
Module: Mathlib.NumberTheory.RamificationInertia.Galois

Goal state before:
pp: R : Type u_1
S : Type u_2
G : Type u_3
inst✝¹⁰ : CommRing R
inst✝⁹ : CommRing S
inst✝⁸ : Algebra R S
inst✝⁷ : Group G
inst✝⁶ : MulSemiringAction G S
inst✝⁵ : IsGaloisGroup G R S
inst✝⁴ : Finite G
p : Ideal R
inst✝³ : p.IsPrime
P : Ideal S
inst✝² : P.LiesOver p
inst✝¹ : P.IsPrime
inst✝ : PerfectField p.ResidueField
this : Algebra (Localization.AtPrime p) (Localization.AtPrime P) := Localization.AtPrime.algebraOfLiesOver p P
⊢ (algebraMap (S ⧸ P) P.ResidueField).comp (algebraMap (R ⧸ p) (S ⧸ P)) =
    (algebraMap p.ResidueField P.ResidueField).comp (algebraMap (R ⧸ p) p.ResidueField)

Tactic:
by

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
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))
comm₂ : (algebraMap (A ⧸ P) (B ⧸ Q)).comp (algebraMap A (A ⧸ P)) = (algebraMap B (B ⧸ Q)).comp (algebraMap A B)
h_eval : (aeval d) (Polynomial.map (algebraMap (A ⧸ P) K) (Polynomial.map (algebraMap A (A ⧸ P)) q)) = 0
h_splits : (Polynomial.map (algebraMap A B) p).Splits
⊢ (algebraMap K L) ((algebraMap (A ⧸ P) K) ((algebraMap A (A ⧸ P)) a)) ∈ nonZeroDivisors L

Tactic:
by

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
⊢ Normal K L

Tactic:
by

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

Goal state before:
pp: A : Type u_1
B : Type u_2
inst✝²¹ : CommRing A
inst✝²⁰ : CommRing B
inst✝¹⁹ : Algebra A B
G : Type u_3
inst✝¹⁸ : Finite G
inst✝¹⁷ : Group G
inst✝¹⁶ : MulSemiringAction G B
inst✝¹⁵ : Algebra.IsInvariant A B G
P : Ideal A
Q : Ideal B
inst✝¹⁴ : Q.LiesOver P
inst✝¹³ : P.IsPrime
inst✝¹² : Q.IsPrime
K : Type u_4
L : Type u_5
inst✝¹¹ : Field K
inst✝¹⁰ : Field L
inst✝⁹ : Algebra K L
inst✝⁸ : Algebra (A ⧸ P) K
inst✝⁷ : IsFractionRing (A ⧸ P) K
inst✝⁶ : Algebra (B ⧸ Q) L
inst✝⁵ : IsFractionRing (B ⧸ Q) L
inst✝⁴ : Algebra (A ⧸ P) L
inst✝³ : IsScalarTower (A ⧸ P) (B ⧸ Q) L
inst✝² : IsScalarTower (A ⧸ P) K L
inst✝¹ : SMulCommClass G A B
inst✝ : Algebra.IsSeparable K L
⊢ Module.Finite K L

Tactic:
by

Goal state after:
Module: Mathlib.NumberTheory.NumberField.Cyclotomic.Embeddings

Goal state before:
pp: n : ℕ
inst✝³ : NeZero n
K : Type u
inst✝² : Field K
inst✝¹ : CharZero K
inst✝ : IsCyclotomicExtension {n} ℚ K
hn : 2 < n
⊢ nrRealPlaces K = 0

Tactic:
by

Goal state after:
Module: Mathlib.NumberTheory.NumberField.Cyclotomic.Embeddings

Goal state before:
pp: n : ℕ
inst✝³ : NeZero n
K : Type u
inst✝² : Field K
inst✝¹ : CharZero K
inst✝ : IsCyclotomicExtension {n} ℚ K
hn : 2 < n
⊢ IsTotallyComplex K

Tactic:
by

Goal state after:
Module: Mathlib.NumberTheory.NumberField.Cyclotomic.Embeddings

Goal state before:
pp: n : ℕ
inst✝² : NeZero n
K : Type u
inst✝¹ : Field K
inst✝ : CharZero K
h : IsCyclotomicExtension {n} ℚ K
this : NumberField K
hn : 2 < n
k : ℕ
hk : φ n = k + k
key : 2 * nrComplexPlaces K = 2 * k
⊢ 2 ≠ 0

Tactic:
by

Goal state after:
Module: Mathlib.NumberTheory.NumberField.Cyclotomic.Embeddings

Goal state before:
pp: n : ℕ
inst✝² : NeZero n
K : Type u
inst✝¹ : Field K
inst✝ : CharZero K
h : IsCyclotomicExtension {n} ℚ K
this : NumberField K
hn : ¬2 < n
h1 : ¬1 < n
⊢ ¬n < 1

Tactic:
by

Goal state after:
Module: Mathlib.NumberTheory.NumberField.Cyclotomic.Embeddings

Goal state before:
pp: n : ℕ
inst✝² : NeZero n
K : Type u
inst✝¹ : Field K
inst✝ : CharZero K
h : IsCyclotomicExtension {n} ℚ K
this : NumberField K
hn : ¬2 < n
⊢ φ n = 1

Tactic:
by

Goal state after:
Module: Mathlib.NumberTheory.NumberField.Cyclotomic.Embeddings

Goal state before:
pp: n : ℕ
inst✝² : NeZero n
K : Type u
inst✝¹ : Field K
inst✝ : CharZero K
h : IsCyclotomicExtension {n} ℚ K
⊢ nrComplexPlaces K = φ n / 2

Tactic:
by

Goal state after:
Module: Mathlib.RingTheory.Ideal.Quotient.HasFiniteQuotients

Goal state before:
pp: R : Type u_1
inst✝¹ : CommRing R
inst✝ : HasFiniteQuotients R
I : Ideal R
hI : ¬I = 0
x : R
hx₁ : x ∈ I
hx₂ : x ≠ 0
⊢ Ideal.span {x} ≠ ⊥

Tactic:
by

Goal state after:
Module: Mathlib.RingTheory.Ideal.Quotient.HasFiniteQuotients

Goal state before:
pp: R : Type u_1
inst✝¹ : CommRing R
inst✝ : HasFiniteQuotients R
⊢ IsNoetherianRing R

Tactic:
by

Goal state after:
Module: Mathlib.NumberTheory.RamificationInertia.Galois

Goal state before:
pp: R : Type u_1
S : Type u_2
G : Type u_3
inst✝¹⁰ : CommRing R
inst✝⁹ : CommRing S
inst✝⁸ : Algebra R S
inst✝⁷ : Group G
inst✝⁶ : MulSemiringAction G S
inst✝⁵ : IsGaloisGroup G R S
inst✝⁴ : Finite G
p : Ideal R
inst✝³ : p.IsPrime
P : Ideal S
inst✝² : P.LiesOver p
inst✝¹ : P.IsPrime
inst✝ : PerfectField p.ResidueField
⊢ Nat.card ↥(MulAction.stabilizer G P) = Nat.card ↥(inertia G P) * P.inertiaDeg R

Tactic:
by

Goal state after:
Module: Mathlib.RingTheory.Ideal.Quotient.HasFiniteQuotients

Goal state before:
pp: R : Type u_1
inst✝⁴ : CommRing R
inst✝³ : HasFiniteQuotients R
inst✝² : IsDomain R
inst✝¹ : PerfectField (FractionRing R)
P : Ideal R
inst✝ : P.IsPrime
⊢ PerfectField P.ResidueField

Tactic:
by

Goal state after:
Module: Mathlib.RingTheory.Ideal.Quotient.HasFiniteQuotients

Goal state before:
pp: R : Type u_1
inst✝¹ : CommRing R
inst✝ : HasFiniteQuotients R
I : Ideal R
hI : I ≠ ⊥
⊢ 0 < Submodule.cardQuot I

Tactic:
by

Goal state after:
Module: Mathlib.NumberTheory.NumberField.ClassNumber

Goal state before:
pp: K : Type u_1
inst✝¹ : Field K
inst✝ : NumberField K
C : ClassGroup (𝓞 K)
⊢ ∃ I,
    ClassGroup.mk0 I = C ∧
      ↑(absNorm ↑I) ≤ (4 / π) ^ nrComplexPlaces K * (↑(finrank ℚ K)! / ↑(finrank ℚ K) ^ finrank ℚ K * √|↑(discr K)|)

Tactic:
by

Goal state after:
Module: Mathlib.RingTheory.Ideal.Quotient.HasFiniteQuotients

Goal state before:
pp: R : Type u_1
inst✝¹ : CommRing R
inst✝ : HasFiniteQuotients R
x : R
hx : x ≠ 0
⊢ {I | x ∈ I}.Finite

Tactic:
by

Goal state after:
Module: Mathlib.NumberTheory.RamificationInertia.Galois

Goal state before:
pp: R : Type u_1
S : Type u_2
G : Type u_3
inst✝¹⁰ : CommRing R
inst✝⁹ : CommRing S
inst✝⁸ : Algebra R S
inst✝⁷ : Group G
inst✝⁶ : MulSemiringAction G S
inst✝⁵ : IsGaloisGroup G R S
inst✝⁴ : Finite G
p : Ideal R
inst✝³ : p.IsPrime
P : Ideal S
inst✝² : P.LiesOver p
inst✝¹ : P.IsPrime
inst✝ : PerfectField p.ResidueField
⊢ (p.primesOver S).ncard * Nat.card ↥(inertia G P) * P.inertiaDeg R = Nat.card G

Tactic:
by

Goal state after:
Module: Mathlib.RingTheory.Ideal.Quotient.HasFiniteQuotients

Goal state before:
pp: R : Type u_1
inst✝¹ : CommRing R
inst✝ : HasFiniteQuotients R
B : ℕ
h✝ : Infinite R
s : Finset R
hs : s.card = B + 1
t : Finset R := (s - s) \ {0}
this : {I | I.cardQuot ≤ B} \ {⊥} ⊆ ⋃ x ∈ t, {I | x ∈ I}
x : R
hx : x ∈ ↑t
⊢ x ≠ 0

Tactic:
by

Goal state after:
Module: Mathlib.NumberTheory.RamificationInertia.Galois

Goal state before:
pp: R : Type u_1
S : Type u_2
G : Type u_3
inst✝¹⁴ : CommRing R
inst✝¹³ : CommRing S
inst✝¹² : Algebra R S
inst✝¹¹ : Group G
inst✝¹⁰ : MulSemiringAction G S
inst✝⁹ : IsGaloisGroup G R S
inst✝⁸ : Finite G
inst✝⁷ : IsDomain R
inst✝⁶ : IsDomain S
inst✝⁵ : Module.Finite R S
inst✝⁴ : Flat R S
p : Ideal R
P : Ideal S
inst✝³ : P.LiesOver p
inst✝² : p.IsPrime
inst✝¹ : P.IsPrime
inst✝ : PerfectField p.ResidueField
H : (p.primesOver S).ncard * Nat.card ↥(inertia G P) * p.inertiaDegIn S = Nat.card G
⊢ (p.primesOver S).ncard ≠ 0

Tactic:
by

Goal state after:
Module: Mathlib.NumberTheory.RamificationInertia.Galois

Goal state before:
pp: R : Type u_1
S : Type u_2
G : Type u_3
inst✝¹⁴ : CommRing R
inst✝¹³ : CommRing S
inst✝¹² : Algebra R S
inst✝¹¹ : Group G
inst✝¹⁰ : MulSemiringAction G S
inst✝⁹ : IsGaloisGroup G R S
inst✝⁸ : Finite G
inst✝⁷ : IsDomain R
inst✝⁶ : IsDomain S
inst✝⁵ : Module.Finite R S
inst✝⁴ : Flat R S
p : Ideal R
P : Ideal S
inst✝³ : P.LiesOver p
inst✝² : p.IsPrime
inst✝¹ : P.IsPrime
inst✝ : PerfectField p.ResidueField
H : (p.primesOver S).ncard * Nat.card ↥(inertia G P) * p.inertiaDegIn S = Nat.card G
h1 : (p.primesOver S).ncard ≠ 0
⊢ p.inertiaDegIn S ≠ 0

Tactic:
by

Goal state after:
Module: Mathlib.RingTheory.Ideal.Quotient.HasFiniteQuotients

Goal state before:
pp: case inr
R : Type u_1
inst✝¹ : CommRing R
inst✝ : HasFiniteQuotients R
B : ℕ
h✝ : Infinite R
s : Finset R
hs : s.card = B + 1
t : Finset R := (s - s) \ {0}
I : Submodule R R
hI : I ∈ {I | I.cardQuot ≤ B} \ {⊥}
⊢ I ∈ ⋃ x ∈ t, {I | x ∈ I}

Tactic:
Set.mem_sdiff,

Goal state after:
case inr
R : Type u_1
inst✝¹ : CommRing R
inst✝ : HasFiniteQuotients R
B : ℕ
h✝ : Infinite R
s : Finset R
hs : s.card = B + 1
t : Finset R := (s - s) \ {0}
I : Submodule R R
hI : I ∈ {I | I.cardQuot ≤ B} ∧ I ∉ {⊥}
⊢ I ∈ ⋃ x ∈ t, {I | x ∈ I}
Module: Mathlib.NumberTheory.RamificationInertia.Galois

Goal state before:
pp: R : Type u_1
S : Type u_2
G : Type u_3
inst✝¹⁴ : CommRing R
inst✝¹³ : CommRing S
inst✝¹² : Algebra R S
inst✝¹¹ : Group G
inst✝¹⁰ : MulSemiringAction G S
inst✝⁹ : IsGaloisGroup G R S
inst✝⁸ : Finite G
inst✝⁷ : IsDomain R
inst✝⁶ : IsDomain S
inst✝⁵ : Module.Finite R S
inst✝⁴ : Flat R S
p : Ideal R
P : Ideal S
inst✝³ : P.LiesOver p
inst✝² : p.IsPrime
inst✝¹ : P.IsPrime
inst✝ : PerfectField p.ResidueField
⊢ Nat.card ↥(inertia G P) = p.ramificationIdxIn S

Tactic:
by

Goal state after:
Module: Mathlib.NumberTheory.RamificationInertia.Galois

Goal state before:
pp: R : Type u_1
S : Type u_2
G : Type u_3
inst✝¹⁴ : CommRing R
inst✝¹³ : CommRing S
inst✝¹² : Algebra R S
inst✝¹¹ : Group G
inst✝¹⁰ : MulSemiringAction G S
inst✝⁹ : IsGaloisGroup G R S
inst✝⁸ : Finite G
inst✝⁷ : IsDomain R
inst✝⁶ : IsDomain S
inst✝⁵ : Module.Finite R S
inst✝⁴ : Flat R S
p : Ideal R
P : Ideal S
inst✝³ : P.LiesOver p
inst✝² : p.IsPrime
inst✝¹ : P.IsPrime
inst✝ : PerfectField p.ResidueField
⊢ Nat.card ↥(MulAction.stabilizer G P) = p.ramificationIdxIn S * p.inertiaDegIn S

Tactic:
by

Goal state after:
Module: Mathlib.RingTheory.Ideal.Quotient.HasFiniteQuotients

Goal state before:
pp: R : Type u_1
inst✝¹ : CommRing R
inst✝ : HasFiniteQuotients R
B : ℕ
h✝ : Infinite R
s : Finset R
hs : s.card = B + 1
t : Finset R := (s - s) \ {0}
I : Submodule R R
hI : Nat.card (R ⧸ I) ≤ B ∧ I ∉ {⊥}
⊢ (Finset.image (⇑(Ideal.Quotient.mk I)) s).card < s.card

Tactic:
by

Goal state after:
Module: Mathlib.NumberTheory.NumberField.ClassNumber

Goal state before:
pp: K : Type u_1
inst✝¹ : Field K
inst✝ : NumberField K
h :
  ∀ ⦃I : ↥(Ideal (𝓞 K))⁰⦄,
    ↑(absNorm ↑I) ≤ (4 / π) ^ nrComplexPlaces K * (↑(finrank ℚ K)! / ↑(finrank ℚ K) ^ finrank ℚ K * √|↑(discr K)|) →
      Submodule.IsPrincipal ↑I
⊢ IsPrincipalIdealRing (𝓞 K)

Tactic:
by

Goal state after:
Module: Mathlib.NumberTheory.RamificationInertia.Galois

Goal state before:
pp: R : Type u_1
K : Type u_2
L : Type u_3
S : Type u_4
inst✝¹⁵ : CommRing R
inst✝¹⁴ : CommRing S
inst✝¹³ : Algebra R S
inst✝¹² : Field K
inst✝¹¹ : Field L
inst✝¹⁰ : Algebra R K
inst✝⁹ : IsFractionRing R K
inst✝⁸ : Algebra S L
inst✝⁷ : Algebra K L
inst✝⁶ : Algebra R L
inst✝⁵ : IsScalarTower R S L
inst✝⁴ : IsScalarTower R K L
inst✝³ : IsIntegralClosure S R L
inst✝² : FiniteDimensional K L
inst✝¹ : IsDedekindDomain R
inst✝ : IsGalois K L
p : Ideal R
P₁ P₂ : Ideal S
hP₁ : P₁ ∈ p.primesOver S
hP₂ : P₂ ∈ p.primesOver S
⊢ ∃ σ, comap ((galRestrict R K L S) σ) P₁ = P₂

Tactic:
by

Goal state after:
Module: Mathlib.RingTheory.Ideal.Quotient.HasFiniteQuotients

Goal state before:
pp: R : Type u_1
inst✝¹ : CommRing R
inst✝ : HasFiniteQuotients R
B : ℕ
⊢ {I | Submodule.cardQuot I ≤ B}.Finite

Tactic:
by

Goal state after:
Module: Mathlib.RingTheory.Ideal.Quotient.HasFiniteQuotients

Goal state before:
pp: R : Type u_1
inst✝¹ : CommRing R
inst✝ : HasFiniteQuotients R
B : ℕ
⊢ Set.MapsTo (fun x ↦ x.asIdeal) {p | Submodule.cardQuot p.asIdeal ≤ B} {I | Submodule.cardQuot I ≤ B}

Tactic:
by

Goal state after:
Module: Mathlib.RingTheory.Ideal.Quotient.HasFiniteQuotients

Goal state before:
pp: R : Type u_1
inst✝⁵ : CommRing R
inst✝⁴ : HasFiniteQuotients R
S : Type u_2
inst✝³ : CommRing S
inst✝² : IsDomain S
inst✝¹ : Algebra R S
inst✝ : Module.Finite R S
I : Ideal S
hI : I ≠ ⊥
⊢ Finite (S ⧸ I)

Tactic:
by

Goal state after:
Module: Mathlib.RingTheory.Ideal.Quotient.HasFiniteQuotients

Goal state before:
pp: R : Type u_1
inst✝ : CommRing R
n : ℤ
hI : ℤ ∙ n ≠ ⊥
⊢ n ≠ 0

Tactic:
by

Goal state after:
Module: Mathlib.RingTheory.Ideal.Quotient.HasFiniteQuotients

Goal state before:
pp: R : Type u_1
inst✝ : CommRing R
I : Ideal ℤ
hI : I ≠ ⊥
⊢ Finite (ℤ ⧸ I)

Tactic:
by

Goal state after:
Module: Mathlib.NumberTheory.NumberField.ClassNumber

Goal state before:
pp: K : Type u_1
inst✝¹ : Field K
inst✝ : NumberField K
h :
  ∀ ⦃I : ↥(Ideal (𝓞 K))⁰⦄,
    (↑I).IsPrime →
      ↑(absNorm ↑I) ≤ (4 / π) ^ nrComplexPlaces K * (↑(finrank ℚ K)! / ↑(finrank ℚ K) ^ finrank ℚ K * √|↑(discr K)|) →
        Submodule.IsPrincipal ↑I
⊢ IsPrincipalIdealRing (𝓞 K)

Tactic:
by

Goal state after:
Module: Mathlib.NumberTheory.NumberField.ClassNumber

Goal state before:
pp: K : Type u_1
inst✝¹ : Field K
inst✝ : NumberField 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),
        p ^ P.inertiaDeg ℤ ≤
            ⌊(4 / π) ^ nrComplexPlaces K * (↑(finrank ℚ K)! / ↑(finrank ℚ K) ^ finrank ℚ K * √|↑(discr K)|)⌋₊ →
          Submodule.IsPrincipal P
x✝ : ↥(Ideal (𝓞 K))⁰
P : Ideal (𝓞 K)
HP : P ∈ (Ideal (𝓞 K))⁰
hP : (↑⟨P, HP⟩).IsPrime
hPN :
  ↑(absNorm ↑⟨P, HP⟩) ≤ (4 / π) ^ nrComplexPlaces K * (↑(finrank ℚ K)! / ↑(finrank ℚ K) ^ finrank ℚ K * √|↑(discr K)|)
p : ℤ
hp : under ℤ P = ℤ ∙ p
h : p = 0
⊢ Ideal.comap (algebraMap ℤ (𝓞 K)) ↑⟨P, HP⟩ = ⊥

Tactic:
by

Goal state after:
Module: Mathlib.NumberTheory.NumberField.ClassNumber

Goal state before:
pp: K : Type u_1
inst✝¹ : Field K
inst✝ : NumberField 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),
        p ^ P.inertiaDeg ℤ ≤
            ⌊(4 / π) ^ nrComplexPlaces K * (↑(finrank ℚ K)! / ↑(finrank ℚ K) ^ finrank ℚ K * √|↑(discr K)|)⌋₊ →
          Submodule.IsPrincipal P
x✝ : ↥(Ideal (𝓞 K))⁰
P : Ideal (𝓞 K)
HP : P ∈ (Ideal (𝓞 K))⁰
hP : (↑⟨P, HP⟩).IsPrime
hPN :
  ↑(absNorm ↑⟨P, HP⟩) ≤ (4 / π) ^ nrComplexPlaces K * (↑(finrank ℚ K)! / ↑(finrank ℚ K) ^ finrank ℚ K * √|↑(discr K)|)
p : ℤ
hp : under ℤ P = ℤ ∙ p
hp0 : p ≠ 0
hpprime : (under ℤ P).IsPrime → _root_.Prime p
⊢ P.LiesOver (span {p})

Tactic:
by

Goal state after:
Module: Mathlib.NumberTheory.NumberField.ClassNumber

Goal state before:
pp: K : Type u_1
inst✝¹ : Field K
inst✝ : NumberField 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),
        p ^ P.inertiaDeg ℤ ≤
            ⌊(4 / π) ^ nrComplexPlaces K * (↑(finrank ℚ K)! / ↑(finrank ℚ K) ^ finrank ℚ K * √|↑(discr K)|)⌋₊ →
          Submodule.IsPrincipal P
x✝ : ↥(Ideal (𝓞 K))⁰
P : Ideal (𝓞 K)
HP : P ∈ (Ideal (𝓞 K))⁰
hP : (↑⟨P, HP⟩).IsPrime
hPN :
  ↑(absNorm ↑⟨P, HP⟩) ≤ (4 / π) ^ nrComplexPlaces K * (↑(finrank ℚ K)! / ↑(finrank ℚ K) ^ finrank ℚ K * √|↑(discr K)|)
p : ℤ
hp : under ℤ P = ℤ ∙ p
hp0 : p ≠ 0
hpprime : (under ℤ P).IsPrime → _root_.Prime p
hlies : P.LiesOver (span {p})
⊢ span {↑p.natAbs} = span {p}

Tactic:
by

Goal state after:
Module: Mathlib.NumberTheory.RamificationInertia.Unramified

Goal state before:
pp: R : Type u_1
S : Type u_2
T : Type u_3
inst✝¹³ : CommRing R
inst✝¹² : CommRing S
inst✝¹¹ : CommRing T
inst✝¹⁰ : Algebra R S
inst✝⁹ : Algebra S T
inst✝⁸ : Algebra R T
inst✝⁷ : IsScalarTower R S T
p : Ideal S
P : Ideal T
inst✝⁶ : P.LiesOver p
inst✝⁵ : p.IsPrime
inst✝⁴ : P.IsPrime
inst✝³ : IsUnramifiedAt R P
inst✝² : EssFiniteType R S
inst✝¹ : EssFiniteType R T
inst✝ : IsDedekindDomain S
hP₁ : P.primeCompl ≤ nonZeroDivisors T
hP₂ : p ≠ ⊥ → P ≠ ⊥
p₀ : Ideal R := Ideal.under R p
this✝⁴ : P.LiesOver p₀
this✝³ : Algebra (Localization.AtPrime p₀) (Localization.AtPrime p) := Localization.AtPrime.algebraOfLiesOver p₀ p
this✝² : Algebra (Localization.AtPrime p) (Localization.AtPrime P) := Localization.AtPrime.algebraOfLiesOver p P
this✝¹ : Algebra (Localization.AtPrime p₀) (Localization.AtPrime P) := Localization.AtPrime.algebraOfLiesOver p₀ P
hp₀ : p₀ = Ideal.under R P
this✝ : EssFiniteType S T
this : IsNoetherianRing T
h₁ : Algebra.IsSeparable p₀.ResidueField P.ResidueField
h₂ : Ideal.map (algebraMap R (Localization.AtPrime P)) p₀ = maximalIdeal (Localization.AtPrime P)
hp : p = ⊥
⊢ Ideal.map (algebraMap R S) p₀ = p

Tactic:
by

Goal state after:
Module: Mathlib.NumberTheory.NumberField.ClassNumber

Goal state before:
pp: K : Type u_1
inst✝¹ : Field K
inst✝ : NumberField 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),
        p ^ P.inertiaDeg ℤ ≤
            ⌊(4 / π) ^ nrComplexPlaces K * (↑(finrank ℚ K)! / ↑(finrank ℚ K) ^ finrank ℚ K * √|↑(discr K)|)⌋₊ →
          Submodule.IsPrincipal P
x✝ : ↥(Ideal (𝓞 K))⁰
P : Ideal (𝓞 K)
HP : P ∈ (Ideal (𝓞 K))⁰
hP : (↑⟨P, HP⟩).IsPrime
hPN :
  ↑(absNorm ↑⟨P, HP⟩) ≤ (4 / π) ^ nrComplexPlaces K * (↑(finrank ℚ K)! / ↑(finrank ℚ K) ^ finrank ℚ K * √|↑(discr K)|)
p : ℤ
hp : under ℤ P = ℤ ∙ p
hp0 : p ≠ 0
hpprime : (under ℤ P).IsPrime → _root_.Prime p
hlies : P.LiesOver (span {p})
hspan : span {↑p.natAbs} = span {p}
⊢ ↑⟨P, HP⟩ ≠ ⊥

Tactic:
by

Goal state after:
Module: Mathlib.NumberTheory.NumberField.ClassNumber

Goal state before:
pp: K : Type u_1
inst✝¹ : Field K
inst✝ : NumberField 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),
        p ^ P.inertiaDeg ℤ ≤
            ⌊(4 / π) ^ nrComplexPlaces K * (↑(finrank ℚ K)! / ↑(finrank ℚ K) ^ finrank ℚ K * √|↑(discr K)|)⌋₊ →
          Submodule.IsPrincipal P
x✝ : ↥(Ideal (𝓞 K))⁰
P : Ideal (𝓞 K)
HP : P ∈ (Ideal (𝓞 K))⁰
hP : (↑⟨P, HP⟩).IsPrime
hPN :
  ↑(absNorm ↑⟨P, HP⟩) ≤ (4 / π) ^ nrComplexPlaces K * (↑(finrank ℚ K)! / ↑(finrank ℚ K) ^ finrank ℚ K * √|↑(discr K)|)
p : ℤ
hp : under ℤ P = ℤ ∙ p
hp0 : p ≠ 0
hpprime : (under ℤ P).IsPrime → _root_.Prime p
hlies : P.LiesOver (span {p})
hspan : span {↑p.natAbs} = span {p}
⊢ p.natAbs ^ P.inertiaDeg ℤ ≤
    ⌊(4 / π) ^ nrComplexPlaces K * (↑(finrank ℚ K)! / ↑(finrank ℚ K) ^ finrank ℚ K * √|↑(discr K)|)⌋₊

Tactic:
by

Goal state after: