mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.RingTheory.Ideal.KrullsHeightTheorem

Goal state before:
pp: R : Type u_1
inst✝² : CommRing R
inst✝¹ : IsNoetherianRing R
q p : Ideal R
inst✝ : q.IsPrime
hqp : q < p
x : R
s : Set R
hp : p ∈ (span (insert x s)).minimalPrimes
t : Set R
htq : t ⊆ ↑q
hsp : s ⊆ ↑(span (insert x t)).radical
⊢ q ∈ (span t).minimalPrimes

Tactic:
let f := Quotient.mk (span t)
  have hf : Function.Surjective f := Quotient.mk_surjective
  have hI'q : span t ≤ q := span_le.mpr htq
  have hI'p : span t ≤ p := hI'q.trans hqp.le
  have := hp.isPrime
  have : (p.map f).IsPrime := map_isPrime_of_surjective hf (by rwa [mk_ker])
  suffices h : (p.map f).height ≤ 1 by
    have h_lt : q.map f < p.map f := (map_mono hqp.le).lt_of_not_ge fun e ↦ hqp.not_ge <| by
      simpa only [comap_map_of_surjective f hf, ← RingHom.ker_eq_comap_bot, f, mk_ker,
        sup_eq_left.mpr hI'q, sup_eq_left.mpr hI'p] using comap_mono (f := f) e
    have : (q.map f).IsPrime := map_isPrime_of_surjective hf (by rwa [mk_ker])
    have : (p.map f).FiniteHeight := ⟨Or.inr (h.trans_lt (WithTop.coe_lt_top 1)).ne⟩
    have := (height_strict_mono_of_isPrime_of_isPrime h_lt).trans_le h
    rw [Order.lt_one_iff, height_eq_zero_iff] at this
    have := minimalPrimes_comap_of_surjective hf this
    rwa [comap_map_of_surjective f hf, ← RingHom.ker_eq_comap_bot,
      mk_ker, sup_eq_left.mpr hI'q] at this
  refine height_le_one_of_isPrincipal_of_mem_minimalPrimes ((span {x}).map f) (p.map f) ⟨⟨this,
    map_mono <| span_le.mpr <| Set.singleton_subset_iff.mpr <| hp.le <| subset_span <| .inl rfl⟩,
    fun r ⟨hr, hxr⟩ hrp ↦ map_le_iff_le_comap.mpr (hp.2 ⟨hr.comap f, ?_⟩ ?_)⟩
  · rw [span_le, Set.insert_subset_iff]
    have := map_le_iff_le_comap.mp hxr (subset_span rfl)
    refine ⟨this, hsp.trans ((hr.comap f).isRadical.radical_le_iff.mpr ?_)⟩
    rw [span_le, Set.insert_subset_iff]
    exact ⟨this, span_le.mp (mk_ker.symm.trans_le (ker_le_comap _))⟩
  · conv_rhs => rw [← sup_eq_left.mpr hI'p, ← (span t).mk_ker, RingHom.ker_eq_comap_bot,
      ← comap_map_of_surjective f hf p]
    exact comap_mono hrp

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

Goal state before:
pp: R : Type u_1
inst✝² : CommRing R
inst✝¹ : IsDomain R
inst✝ : IsPrincipalIdealRing R
h : ¬IsField R
⊢ ringKrullDim R ≤ 1

Tactic:
rw [← Nat.cast_one, ← Ring.krullDimLE_iff]
    infer_instance

Goal state after:
Module: Mathlib.RingTheory.KrullDimension.Polynomial

Goal state before:
pp: R : Type u_1
inst✝³ : CommRing R
inst✝² : IsNoetherianRing R
p : Ideal R
P : Ideal R[X]
inst✝¹ : P.IsMaximal
inst✝ : P.LiesOver p
this : p.IsPrime
Rₚ : Type u_1 := Localization.AtPrime p
p' : Ideal Rₚ := Ideal.map (algebraMap R Rₚ) p
p'_def : p' = Ideal.map (algebraMap R Rₚ) p
⊢ (Ideal.map (algebraMap R Rₚ) p).IsMaximal

Tactic:
Localization.AtPrime.map_eq_maximalIdeal

Goal state after:
R : Type u_1
inst✝³ : CommRing R
inst✝² : IsNoetherianRing R
p : Ideal R
P : Ideal R[X]
inst✝¹ : P.IsMaximal
inst✝ : P.LiesOver p
this : p.IsPrime
Rₚ : Type u_1 := Localization.AtPrime p
p' : Ideal Rₚ := Ideal.map (algebraMap R Rₚ) p
p'_def : p' = Ideal.map (algebraMap R Rₚ) p
⊢ (IsLocalRing.maximalIdeal (Localization p.primeCompl)).IsMaximal
Module: Mathlib.RingTheory.Spectrum.Prime.LTSeries

Goal state before:
pp: case succ
R : Type u_1
inst✝¹ : CommRing R
inst✝ : IsNoetherianRing R
x : R
n : ℕ
hn :
  ∀ (p : LTSeries (PrimeSpectrum R)),
    x ∈ (RelSeries.last p).asIdeal →
      p.length = n →
        ∃ q,
          x ∈ (q.toFun 1).asIdeal ∧
            n = q.length ∧ RelSeries.head p = RelSeries.head q ∧ RelSeries.last p = RelSeries.last q
p : LTSeries (PrimeSpectrum R)
hx : x ∈ (RelSeries.last p).asIdeal
hp : p.length = n + 1
⊢ ∃ q,
    x ∈ (q.toFun 1).asIdeal ∧
      n + 1 = q.length ∧ RelSeries.head p = RelSeries.head q ∧ RelSeries.last p = RelSeries.last q

Tactic:
by_cases h0 : n = 0

Goal state after:
case pos
R : Type u_1
inst✝¹ : CommRing R
inst✝ : IsNoetherianRing R
x : R
n : ℕ
hn :
  ∀ (p : LTSeries (PrimeSpectrum R)),
    x ∈ (RelSeries.last p).asIdeal →
      p.length = n →
        ∃ q,
          x ∈ (q.toFun 1).asIdeal ∧
            n = q.length ∧ RelSeries.head p = RelSeries.head q ∧ RelSeries.last p = RelSeries.last q
p : LTSeries (PrimeSpectrum R)
hx : x ∈ (RelSeries.last p).asIdeal
hp : p.length = n + 1
h0 : n = 0
⊢ ∃ q,
    x ∈ (q.toFun 1).asIdeal ∧
      n + 1 = q.length ∧ RelSeries.head p = RelSeries.head q ∧ RelSeries.last p = RelSeries.last q

case neg
R : Type u_1
inst✝¹ : CommRing R
inst✝ : IsNoetherianRing R
x : R
n : ℕ
hn :
  ∀ (p : LTSeries (PrimeSpectrum R)),
    x ∈ (RelSeries.last p).asIdeal →
      p.length = n →
        ∃ q,
          x ∈ (q.toFun 1).asIdeal ∧
            n = q.length ∧ RelSeries.head p = RelSeries.head q ∧ RelSeries.last p = RelSeries.last q
p : LTSeries (PrimeSpectrum R)
hx : x ∈ (RelSeries.last p).asIdeal
hp : p.length = n + 1
h0 : ¬n = 0
⊢ ∃ q,
    x ∈ (q.toFun 1).asIdeal ∧
      n + 1 = q.length ∧ RelSeries.head p = RelSeries.head q ∧ RelSeries.last p = RelSeries.last q
Module: Mathlib.RingTheory.KrullDimension.Regular

Goal state before:
pp: case cons
R : Type u_1
inst✝⁵ : CommRing R
inst✝⁴ : IsNoetherianRing R
inst✝³ : IsLocalRing R
x : R
rs' : List R
ih :
  ∀ {M : Type u_2} [inst : AddCommGroup M] [inst_1 : Module R M] [Module.Finite R M],
    Sequence.IsRegular M rs' → supportDim R (M ⧸ ofList rs' • ⊤) + ↑rs'.length = supportDim R M
M : Type u_2
inst✝² : AddCommGroup M
inst✝¹ : Module R M
inst✝ : Module.Finite R M
reg : Sequence.IsRegular M (x :: rs')
⊢ supportDim R (M ⧸ ofList (x :: rs') • ⊤) + ↑(x :: rs').length = supportDim R M

Tactic:
have mem : x ∈ maximalIdeal R := by
      simpa using fun isu ↦ reg.2 (by simp [span_singleton_eq_top.mpr isu])

Goal state after:
case cons
R : Type u_1
inst✝⁵ : CommRing R
inst✝⁴ : IsNoetherianRing R
inst✝³ : IsLocalRing R
x : R
rs' : List R
ih :
  ∀ {M : Type u_2} [inst : AddCommGroup M] [inst_1 : Module R M] [Module.Finite R M],
    Sequence.IsRegular M rs' → supportDim R (M ⧸ ofList rs' • ⊤) + ↑rs'.length = supportDim R M
M : Type u_2
inst✝² : AddCommGroup M
inst✝¹ : Module R M
inst✝ : Module.Finite R M
reg : Sequence.IsRegular M (x :: rs')
mem : x ∈ maximalIdeal R
⊢ supportDim R (M ⧸ ofList (x :: rs') • ⊤) + ↑(x :: rs').length = supportDim R M
Module: Mathlib.RingTheory.Lasker

Goal state before:
pp: R : Type u_1
M : Type u_2
inst✝³ : CommRing R
inst✝² : AddCommGroup M
inst✝¹ : Module R M
inst✝ : IsNoetherian R M
N : Submodule R M
h : InfIrred N
⊢ N.IsPrimary

Tactic:
rw [Submodule.IsPrimary]

Goal state after:
R : Type u_1
M : Type u_2
inst✝³ : CommRing R
inst✝² : AddCommGroup M
inst✝¹ : Module R M
inst✝ : IsNoetherian R M
N : Submodule R M
h : InfIrred N
⊢ N ≠ ⊤ ∧ ∀ {r : R} {x : M}, r • x ∈ N → x ∈ N ∨ ∃ n, r ^ n • ⊤ ≤ N
Module: Mathlib.RingTheory.LaurentSeries

Goal state before:
pp: case mp
R : Type u_1
inst✝ : Semiring R
x : R⸨X⸩
⊢ x.powerSeriesPart = 0 → x = 0

Tactic:
contrapose!

Goal state after:
case mp
R : Type u_1
inst✝ : Semiring R
x : R⸨X⸩
⊢ x ≠ 0 → x.powerSeriesPart ≠ 0
Module: Mathlib.RingTheory.Invariant.Profinite

Goal state before:
pp: case refine_2
A : Type u_1
B : Type u_2
inst✝¹⁵ : CommRing A
inst✝¹⁴ : CommRing B
inst✝¹³ : Algebra A B
G : Type u
inst✝¹² : Group G
inst✝¹¹ : MulSemiringAction G B
inst✝¹⁰ : SMulCommClass G A B
inst✝⁹ : TopologicalSpace G
inst✝⁸ : CompactSpace G
inst✝⁷ : TotallyDisconnectedSpace G
inst✝⁶ : IsTopologicalGroup G
inst✝⁵ : TopologicalSpace B
inst✝⁴ : DiscreteTopology B
inst✝³ : ContinuousSMul G B
P : Ideal A
Q : Ideal B
inst✝² : Q.IsPrime
inst✝¹ : Q.LiesOver P
inst✝ : Algebra.IsInvariant A B G
σ : (B ⧸ Q) ≃ₐ[A ⧸ P] B ⧸ Q
B' : (G : Type u) → [inst : Monoid G] → [inst_1 : MulSemiringAction G B] → [SMulCommClass G A B] → Subalgebra A B :=
  FixedPoints.subalgebra A B
s : (j : OpenNormalSubgroup G) → (stabilizerHomSurjectiveAuxFunctor P Q σ).obj j
hs : s ∈ (stabilizerHomSurjectiveAuxFunctor P Q σ).sections
a : ↑(ProfiniteGrp.of G).toProfinite.toTop :=
  (ProfiniteGrp.Hom.hom (ProfiniteGrp.of G).isoLimittoFiniteQuotientFunctor.inv) ⟨fun N ↦ ↑↑(s N), ⋯⟩
this : ∀ (N : OpenNormalSubgroup G), ↑a = ↑↑(s N)
N : OpenNormalSubgroup G
x : ↥(B' ↥↑N.toOpenSubgroup)
hN : ↑N ⊆ ↑(MulAction.stabilizer G ↑x)
⊢ (mk Q) ↑(↑↑(s N) • x) = σ ((mk Q) ↑x)

Tactic:
exact DFunLike.congr_fun (s N).2 (Ideal.Quotient.mk _ x)

Goal state after:
Module: Mathlib.RingTheory.LaurentSeries

Goal state before:
pp: R : Type u_1
K : Type u_2
inst✝ : Field K
⊢ ¬Ideal.span {X} = ⊥

Tactic:
Ideal.span_singleton_eq_bot

Goal state after:
R : Type u_1
K : Type u_2
inst✝ : Field K
⊢ ¬X = 0
Module: Mathlib.RingTheory.Localization.AtPrime.Extension

Goal state before:
pp: case h
R : Type u_1
S : Type u_2
inst✝⁷ : CommRing R
inst✝⁶ : CommRing S
inst✝⁵ : Algebra R S
p : Ideal R
inst✝⁴ : p.IsPrime
Sₚ : Type u_4
inst✝³ : CommRing Sₚ
inst✝² : Algebra S Sₚ
inst✝¹ : IsLocalization (algebraMapSubmonoid S p.primeCompl) Sₚ
P : Ideal S
hPp : P.LiesOver p
inst✝ : P.IsMaximal
x : S
s : ↥(algebraMapSubmonoid S p.primeCompl)
s' : S
hs : (Ideal.Quotient.mk P) s' = ((Ideal.Quotient.mk P) ↑s)⁻¹
⊢ (Ideal.Quotient.mk (Ideal.map (algebraMap S Sₚ) P)) ((algebraMap S Sₚ) (x * s')) =
    (Ideal.Quotient.mk (Ideal.map (algebraMap S Sₚ) P)) (mk' Sₚ x s)

Tactic:
← sub_eq_zero,

Goal state after:
case h
R : Type u_1
S : Type u_2
inst✝⁷ : CommRing R
inst✝⁶ : CommRing S
inst✝⁵ : Algebra R S
p : Ideal R
inst✝⁴ : p.IsPrime
Sₚ : Type u_4
inst✝³ : CommRing Sₚ
inst✝² : Algebra S Sₚ
inst✝¹ : IsLocalization (algebraMapSubmonoid S p.primeCompl) Sₚ
P : Ideal S
hPp : P.LiesOver p
inst✝ : P.IsMaximal
x : S
s : ↥(algebraMapSubmonoid S p.primeCompl)
s' : S
hs : (Ideal.Quotient.mk P) s' = ((Ideal.Quotient.mk P) ↑s)⁻¹
⊢ (Ideal.Quotient.mk (Ideal.map (algebraMap S Sₚ) P)) ((algebraMap S Sₚ) (x * s')) -
      (Ideal.Quotient.mk (Ideal.map (algebraMap S Sₚ) P)) (mk' Sₚ x s) =
    0
Module: Mathlib.RingTheory.Localization.AtPrime.Extension

Goal state before:
pp: case h
R : Type u_1
S : Type u_2
inst✝⁷ : CommRing R
inst✝⁶ : CommRing S
inst✝⁵ : Algebra R S
p : Ideal R
inst✝⁴ : p.IsPrime
Sₚ : Type u_4
inst✝³ : CommRing Sₚ
inst✝² : Algebra S Sₚ
inst✝¹ : IsLocalization (algebraMapSubmonoid S p.primeCompl) Sₚ
P : Ideal S
hPp : P.LiesOver p
inst✝ : P.IsMaximal
x : S
s : ↥(algebraMapSubmonoid S p.primeCompl)
s' : S
hs : (Ideal.Quotient.mk P) s' = ((Ideal.Quotient.mk P) ↑s)⁻¹
⊢ (Ideal.Quotient.mk (Ideal.map (algebraMap S Sₚ) P)) ((algebraMap S Sₚ) (x * s') - mk' Sₚ x s) = 0

Tactic:
Quotient.eq_zero_iff_mem

Goal state after:
case h
R : Type u_1
S : Type u_2
inst✝⁷ : CommRing R
inst✝⁶ : CommRing S
inst✝⁵ : Algebra R S
p : Ideal R
inst✝⁴ : p.IsPrime
Sₚ : Type u_4
inst✝³ : CommRing Sₚ
inst✝² : Algebra S Sₚ
inst✝¹ : IsLocalization (algebraMapSubmonoid S p.primeCompl) Sₚ
P : Ideal S
hPp : P.LiesOver p
inst✝ : P.IsMaximal
x : S
s : ↥(algebraMapSubmonoid S p.primeCompl)
s' : S
hs : (Ideal.Quotient.mk P) s' = ((Ideal.Quotient.mk P) ↑s)⁻¹
⊢ (algebraMap S Sₚ) (x * s') - mk' Sₚ x s ∈ Ideal.map (algebraMap S Sₚ) P
Module: Mathlib.RingTheory.Localization.AtPrime.Extension

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
p : Ideal R
inst✝⁴ : p.IsPrime
Sₚ : Type u_4
inst✝³ : CommRing Sₚ
inst✝² : Algebra S Sₚ
inst✝¹ : IsLocalization (algebraMapSubmonoid S p.primeCompl) Sₚ
P : Ideal S
hPp : P.LiesOver p
inst✝ : P.IsMaximal
x : S
s : ↥(algebraMapSubmonoid S p.primeCompl)
this : (Ideal.map (algebraMap S Sₚ) P).IsPrime
h₁ : (Ideal.Quotient.mk P) ↑s ≠ 0
⊢ (equivQuotientMapOfIsMaximal p Sₚ P).symm ((Ideal.Quotient.mk (Ideal.map (algebraMap S Sₚ) P)) (mk' Sₚ x s)) =
    (Ideal.Quotient.mk P) x * ((Ideal.Quotient.mk P) ↑s)⁻¹

Tactic:
have h₂ : equivQuotientMapOfIsMaximal p Sₚ P (Ideal.Quotient.mk P ↑s) ≠ 0 := by
    rwa [RingEquiv.map_ne_zero_iff]

Goal state after:
R : Type u_1
S : Type u_2
inst✝⁷ : CommRing R
inst✝⁶ : CommRing S
inst✝⁵ : Algebra R S
p : Ideal R
inst✝⁴ : p.IsPrime
Sₚ : Type u_4
inst✝³ : CommRing Sₚ
inst✝² : Algebra S Sₚ
inst✝¹ : IsLocalization (algebraMapSubmonoid S p.primeCompl) Sₚ
P : Ideal S
hPp : P.LiesOver p
inst✝ : P.IsMaximal
x : S
s : ↥(algebraMapSubmonoid S p.primeCompl)
this : (Ideal.map (algebraMap S Sₚ) P).IsPrime
h₁ : (Ideal.Quotient.mk P) ↑s ≠ 0
h₂ : (equivQuotientMapOfIsMaximal p Sₚ P) ((Ideal.Quotient.mk P) ↑s) ≠ 0
⊢ (equivQuotientMapOfIsMaximal p Sₚ P).symm ((Ideal.Quotient.mk (Ideal.map (algebraMap S Sₚ) P)) (mk' Sₚ x s)) =
    (Ideal.Quotient.mk P) x * ((Ideal.Quotient.mk P) ↑s)⁻¹
Module: Mathlib.RingTheory.Localization.AtPrime.Extension

Goal state before:
pp: R : Type u_1
S : Type u_2
inst✝¹⁵ : CommRing R
inst✝¹⁴ : CommRing S
inst✝¹³ : Algebra R S
p : Ideal R
inst✝¹² : p.IsPrime
Rₚ : Type u_3
inst✝¹¹ : CommRing Rₚ
inst✝¹⁰ : Algebra R Rₚ
inst✝⁹ : IsLocalization.AtPrime Rₚ p
inst✝⁸ : IsLocalRing Rₚ
Sₚ : Type u_4
inst✝⁷ : CommRing Sₚ
inst✝⁶ : Algebra S Sₚ
inst✝⁵ : IsLocalization (algebraMapSubmonoid S p.primeCompl) Sₚ
inst✝⁴ : Algebra Rₚ Sₚ
P : Ideal S
hPp : P.LiesOver p
inst✝³ : Algebra R Sₚ
inst✝² : IsScalarTower R S Sₚ
inst✝¹ : IsScalarTower R Rₚ Sₚ
inst✝ : P.IsPrime
this✝³ : (Ideal.map (algebraMap S Sₚ) P).LiesOver (maximalIdeal Rₚ)
this✝² : (Ideal.map (algebraMap S Sₚ) P).LiesOver P
this✝¹ : (Ideal.map (algebraMap S Sₚ) P).IsPrime
R₁ : Type u_4 := Localization.AtPrime (Ideal.map (algebraMap S Sₚ) P)
R₂ : Type u_2 := Localization.AtPrime P
this✝ : Algebra R₂ R₁ := algebraOfLiesOver P (Ideal.map (algebraMap S Sₚ) P)
this : IsLocalization.AtPrime R₁ P
h : Function.Bijective ⇑(algebraMap R₂ R₁)
⊢ (length (Localization.AtPrime (Ideal.map (algebraMap S Sₚ) P))
        (Localization.AtPrime (Ideal.map (algebraMap S Sₚ) P) ⧸
          Ideal.map (algebraMap Rₚ (Localization.AtPrime (Ideal.map (algebraMap S Sₚ) P))) (maximalIdeal Rₚ))).toNat =
    (length (Localization.AtPrime P)
        (Localization.AtPrime P ⧸ Ideal.map (algebraMap R (Localization.AtPrime P)) p)).toNat

Tactic:
have key : p.map (algebraMap R R₂) =
      ((maximalIdeal Rₚ).map (algebraMap Rₚ R₁)).comap (algebraMap R₂ R₁) := by
    rw [← IsLocalization.AtPrime.map_eq_maximalIdeal p, p.map_map, ← IsScalarTower.algebraMap_eq,
      IsScalarTower.algebraMap_eq R R₂ R₁, ← p.map_map, comap_map_of_bijective _ h]

Goal state after:
R : Type u_1
S : Type u_2
inst✝¹⁵ : CommRing R
inst✝¹⁴ : CommRing S
inst✝¹³ : Algebra R S
p : Ideal R
inst✝¹² : p.IsPrime
Rₚ : Type u_3
inst✝¹¹ : CommRing Rₚ
inst✝¹⁰ : Algebra R Rₚ
inst✝⁹ : IsLocalization.AtPrime Rₚ p
inst✝⁸ : IsLocalRing Rₚ
Sₚ : Type u_4
inst✝⁷ : CommRing Sₚ
inst✝⁶ : Algebra S Sₚ
inst✝⁵ : IsLocalization (algebraMapSubmonoid S p.primeCompl) Sₚ
inst✝⁴ : Algebra Rₚ Sₚ
P : Ideal S
hPp : P.LiesOver p
inst✝³ : Algebra R Sₚ
inst✝² : IsScalarTower R S Sₚ
inst✝¹ : IsScalarTower R Rₚ Sₚ
inst✝ : P.IsPrime
this✝³ : (Ideal.map (algebraMap S Sₚ) P).LiesOver (maximalIdeal Rₚ)
this✝² : (Ideal.map (algebraMap S Sₚ) P).LiesOver P
this✝¹ : (Ideal.map (algebraMap S Sₚ) P).IsPrime
R₁ : Type u_4 := Localization.AtPrime (Ideal.map (algebraMap S Sₚ) P)
R₂ : Type u_2 := Localization.AtPrime P
this✝ : Algebra R₂ R₁ := algebraOfLiesOver P (Ideal.map (algebraMap S Sₚ) P)
this : IsLocalization.AtPrime R₁ P
h : Function.Bijective ⇑(algebraMap R₂ R₁)
key : Ideal.map (algebraMap R R₂) p = comap (algebraMap R₂ R₁) (Ideal.map (algebraMap Rₚ R₁) (maximalIdeal Rₚ))
⊢ (length (Localization.AtPrime (Ideal.map (algebraMap S Sₚ) P))
        (Localization.AtPrime (Ideal.map (algebraMap S Sₚ) P) ⧸
          Ideal.map (algebraMap Rₚ (Localization.AtPrime (Ideal.map (algebraMap S Sₚ) P))) (maximalIdeal Rₚ))).toNat =
    (length (Localization.AtPrime P)
        (Localization.AtPrime P ⧸ Ideal.map (algebraMap R (Localization.AtPrime P)) p)).toNat
Module: Mathlib.RingTheory.LaurentSeries

Goal state before:
pp: K : Type u_2
inst✝ : Field K
ℱ : Filter K⸨X⸩
hℱ : Cauchy ℱ
x✝ : UniformSpace K := ⊥
⊢ ∃ N, ∀ n < N, coeff hℱ n = 0

Tactic:
obtain ⟨N, hN⟩ := exists_lb_eventual_support hℱ

Goal state after:
K : Type u_2
inst✝ : Field K
ℱ : Filter K⸨X⸩
hℱ : Cauchy ℱ
x✝ : UniformSpace K := ⊥
N : ℤ
hN : ∀ᶠ (f : K⸨X⸩) in ℱ, ∀ n < N, f.coeff n = 0
⊢ ∃ N, ∀ n < N, coeff hℱ n = 0
Module: Mathlib.RingTheory.LaurentSeries

Goal state before:
pp: K : Type u_2
inst✝ : Field K
ℱ : Filter K⸨X⸩
hℱ : Cauchy ℱ
N₁ : ℤ
hN₁ : ∀ᶠ (f : K⸨X⸩) in ℱ, ∀ n < N₁, f.coeff n = 0
N₂ : ℤ
hN₂ : ∀ n < N₂, coeff hℱ n = 0
⊢ ∃ N, ∀ᶠ (f : K⸨X⸩) in ℱ, ∀ d < N, coeff hℱ d = f.coeff d

Tactic:
refine ⟨min N₁ N₂, ℱ.3 hN₁ fun _ hf d hd ↦ ?_⟩

Goal state after:
K : Type u_2
inst✝ : Field K
ℱ : Filter K⸨X⸩
hℱ : Cauchy ℱ
N₁ : ℤ
hN₁ : ∀ᶠ (f : K⸨X⸩) in ℱ, ∀ n < N₁, f.coeff n = 0
N₂ : ℤ
hN₂ : ∀ n < N₂, coeff hℱ n = 0
x✝ : K⸨X⸩
hf : x✝ ∈ {x | (fun f ↦ ∀ n < N₁, f.coeff n = 0) x}
d : ℤ
hd : d < min N₁ N₂
⊢ coeff hℱ d = x✝.coeff d
Module: Mathlib.RingTheory.MvPolynomial.Symmetric.FundamentalTheorem

Goal state before:
pp: case refine_2
R : Type u_3
m : ℕ
inst✝¹ : CommSemiring R
inst✝ : Nontrivial R
i : ℕ
him : i < m
t : Finset (Fin m)
ht : t ∈ powersetCard (i + 1) univ
ht' : #t = #(Iic ⟨i, him⟩)
hne : ∃ x, x ∈ Iic ⟨i, him⟩ \ t
hkm : (Iic ⟨i, him⟩ \ t).min' hne ∈ Iic ⟨i, him⟩ ∧ (Iic ⟨i, him⟩ \ t).min' hne ∉ t
⊢ toLex (Finsupp.indicator t fun x x_1 ↦ 1) < toLex (Finsupp.indicator (Iic ⟨i, him⟩) fun x x_1 ↦ 1)

Tactic:
refine ⟨min' _ hne, fun k hk ↦ ?_, ?_⟩

Goal state after:
case refine_2.refine_1
R : Type u_3
m : ℕ
inst✝¹ : CommSemiring R
inst✝ : Nontrivial R
i : ℕ
him : i < m
t : Finset (Fin m)
ht : t ∈ powersetCard (i + 1) univ
ht' : #t = #(Iic ⟨i, him⟩)
hne : ∃ x, x ∈ Iic ⟨i, him⟩ \ t
hkm : (Iic ⟨i, him⟩ \ t).min' hne ∈ Iic ⟨i, him⟩ ∧ (Iic ⟨i, him⟩ \ t).min' hne ∉ t
k : Fin m
hk : (fun x1 x2 ↦ x1 < x2) k ((Iic ⟨i, him⟩ \ t).min' hne)
⊢ (ofLex (toLex (Finsupp.indicator t fun x x_1 ↦ 1))) k =
    (ofLex (toLex (Finsupp.indicator (Iic ⟨i, him⟩) fun x x_1 ↦ 1))) k

case refine_2.refine_2
R : Type u_3
m : ℕ
inst✝¹ : CommSemiring R
inst✝ : Nontrivial R
i : ℕ
him : i < m
t : Finset (Fin m)
ht : t ∈ powersetCard (i + 1) univ
ht' : #t = #(Iic ⟨i, him⟩)
hne : ∃ x, x ∈ Iic ⟨i, him⟩ \ t
hkm : (Iic ⟨i, him⟩ \ t).min' hne ∈ Iic ⟨i, him⟩ ∧ (Iic ⟨i, him⟩ \ t).min' hne ∉ t
⊢ (fun {i} x1 x2 ↦ x1 < x2) ((ofLex (toLex (Finsupp.indicator t fun x x_1 ↦ 1))) ((Iic ⟨i, him⟩ \ t).min' hne))
    ((ofLex (toLex (Finsupp.indicator (Iic ⟨i, him⟩) fun x x_1 ↦ 1))) ((Iic ⟨i, him⟩ \ t).min' hne))
Module: Mathlib.RingTheory.LaurentSeries

Goal state before:
pp: case h
K : Type u_2
inst✝ : Field K
f : K⸨X⸩
γ : (WithZero (Multiplicative ℤ))ˣ
F : K⟦X⟧ := f.powerSeriesPart
hF : F = f.powerSeriesPart
ord_nonpos : HahnSeries.order f < 0
η : (WithZero (Multiplicative ℤ))ˣ := Units.mk0 (exp (HahnSeries.order f)) ⋯
hη : η = Units.mk0 (exp (HahnSeries.order f)) ⋯
P : K[X]
hP : (PowerSeries.idealX K).intValuation (F - ↑P) < ↑(η * γ)
s : ℕ
F_mul : ((ofPowerSeries ℤ K) (PowerSeries.X ^ s))⁻¹ * (ofPowerSeries ℤ K) F = f
hs : HahnSeries.order f = -↑s
this : (algebraMap K⟮X⟯ K⸨X⸩) 1 = 1
⊢ (exp (HahnSeries.order f))⁻¹ * (PowerSeries.idealX K).intValuation (F - ↑P) < ↑γ

Tactic:
← Units.val_mk0 (a := exp f.order) exp_ne_zero,

Goal state after:
case h
K : Type u_2
inst✝ : Field K
f : K⸨X⸩
γ : (WithZero (Multiplicative ℤ))ˣ
F : K⟦X⟧ := f.powerSeriesPart
hF : F = f.powerSeriesPart
ord_nonpos : HahnSeries.order f < 0
η : (WithZero (Multiplicative ℤ))ˣ := Units.mk0 (exp (HahnSeries.order f)) ⋯
hη : η = Units.mk0 (exp (HahnSeries.order f)) ⋯
P : K[X]
hP : (PowerSeries.idealX K).intValuation (F - ↑P) < ↑(η * γ)
s : ℕ
F_mul : ((ofPowerSeries ℤ K) (PowerSeries.X ^ s))⁻¹ * (ofPowerSeries ℤ K) F = f
hs : HahnSeries.order f = -↑s
this : (algebraMap K⟮X⟯ K⸨X⸩) 1 = 1
⊢ (↑(Units.mk0 (exp (HahnSeries.order f)) ⋯))⁻¹ * (PowerSeries.idealX K).intValuation (F - ↑P) < ↑γ
Module: Mathlib.RingTheory.LaurentSeries

Goal state before:
pp: case h
K : Type u_2
inst✝ : Field K
S : Set (K⟮X⟯ × K⟮X⟯)
w✝ : Set K⟮X⟯
hT : w✝ ∈ nhds 0
pre_T : (fun x ↦ x.2 - x.1) ⁻¹' w✝ ⊆ S
d : (MonoidWithZeroHom.ofClass Valued.v).ValueGroup₀ˣ
hd : {y | Valued.v.restrict (y - 0) < ↑d} ⊆ w✝
X : Set K⸨X⸩ := {f | Valued.v f < embedding ↑d}
X_def : X = {f | Valued.v f < embedding ↑d}
x : K⟮X⟯
hx : (restrict₀ (MonoidWithZeroHom.ofClass Valued.v)) x = ↑d
⊢ ∀ (a : K⸨X⸩), Valued.v a < Valued.v ((algebraMap K⟮X⟯ K⸨X⸩) x) → Valued.v a < embedding ↑d

Tactic:
rw [← hx, embedding_restrict₀]

Goal state after:
case h
K : Type u_2
inst✝ : Field K
S : Set (K⟮X⟯ × K⟮X⟯)
w✝ : Set K⟮X⟯
hT : w✝ ∈ nhds 0
pre_T : (fun x ↦ x.2 - x.1) ⁻¹' w✝ ⊆ S
d : (MonoidWithZeroHom.ofClass Valued.v).ValueGroup₀ˣ
hd : {y | Valued.v.restrict (y - 0) < ↑d} ⊆ w✝
X : Set K⸨X⸩ := {f | Valued.v f < embedding ↑d}
X_def : X = {f | Valued.v f < embedding ↑d}
x : K⟮X⟯
hx : (restrict₀ (MonoidWithZeroHom.ofClass Valued.v)) x = ↑d
⊢ ∀ (a : K⸨X⸩), Valued.v a < Valued.v ((algebraMap K⟮X⟯ K⸨X⸩) x) → Valued.v a < (MonoidWithZeroHom.ofClass Valued.v) x
Module: Mathlib.RingTheory.MvPolynomial.Symmetric.NewtonIdentities

Goal state before:
pp: σ : Type u_1
R : Type u_2
inst✝² : CommRing R
inst✝¹ : DecidableEq σ
inst✝ : Fintype σ
k : ℕ
f : Finset σ × σ → MvPolynomial σ R
⊢ ∑ t ∈ pairs σ k with #t.1 = k, f t = ∑ A ∈ powersetCard k univ, ∑ j ∈ A, f (A, j)

Tactic:
by
  apply sum_finset_product
  aesop

Goal state after:
Module: Mathlib.RingTheory.MvPolynomial.Symmetric.NewtonIdentities

Goal state before:
pp: σ : Type u_1
inst✝¹ : Fintype σ
R : Type u_2
inst✝ : CommRing R
k : ℕ
⊢ (-1) ^ (k + 1) * ∑ t ∈ NewtonIdentities.pairs σ k with #t.1 < k, NewtonIdentities.weight σ R k t =
    (-1) ^ k * ∑ t ∈ NewtonIdentities.pairs σ k with #t.1 = k, NewtonIdentities.weight σ R k t

Tactic:
← sub_eq_zero,

Goal state after:
σ : Type u_1
inst✝¹ : Fintype σ
R : Type u_2
inst✝ : CommRing R
k : ℕ
⊢ (-1) ^ (k + 1) * ∑ t ∈ NewtonIdentities.pairs σ k with #t.1 < k, NewtonIdentities.weight σ R k t -
      (-1) ^ k * ∑ t ∈ NewtonIdentities.pairs σ k with #t.1 = k, NewtonIdentities.weight σ R k t =
    0
Module: Mathlib.RingTheory.NoetherNormalization

Goal state before:
pp: k : Type u_1
inst✝ : Field k
n : ℕ
f : MvPolynomial (Fin (n + 1)) k
fne : f ≠ 0
v : Fin (n + 1) →₀ ℕ
vin : v ∈ f.support
h : (Fin (n + 1) →₀ ℕ) → MvPolynomial (Fin (n + 1)) k := fun w ↦ (MvPolynomial.monomial w) (MvPolynomial.coeff w f)
vs :
  ∀ x ∈ f.support \ {v},
    ((MvPolynomial.finSuccEquiv k n) ((T f) (h x))).degree < ((MvPolynomial.finSuccEquiv k n) ((T f) (h v))).degree
⊢ (∑ x ∈ f.support \ {v}, (MvPolynomial.finSuccEquiv k n) ((T f) (h x)) +
        (MvPolynomial.finSuccEquiv k n) ((T f) (h v))).leadingCoeff =
    ((MvPolynomial.finSuccEquiv k n) ((T f) (h v))).leadingCoeff

Tactic:
apply leadingCoeff_add_of_degree_lt <| (lt_of_le_of_lt <| degree_sum_le _ _) ?_

Goal state after:
k : Type u_1
inst✝ : Field k
n : ℕ
f : MvPolynomial (Fin (n + 1)) k
fne : f ≠ 0
v : Fin (n + 1) →₀ ℕ
vin : v ∈ f.support
h : (Fin (n + 1) →₀ ℕ) → MvPolynomial (Fin (n + 1)) k := fun w ↦ (MvPolynomial.monomial w) (MvPolynomial.coeff w f)
vs :
  ∀ x ∈ f.support \ {v},
    ((MvPolynomial.finSuccEquiv k n) ((T f) (h x))).degree < ((MvPolynomial.finSuccEquiv k n) ((T f) (h v))).degree
⊢ ((f.support \ {v}).sup fun b ↦ ((MvPolynomial.finSuccEquiv k n) ((T f) (h b))).degree) <
    ((MvPolynomial.finSuccEquiv k n) ((T f) (h v))).degree
Module: Mathlib.RingTheory.WittVector.WittPolynomial

Goal state before:
pp: p : ℕ
R : Type u_1
inst✝¹ : CommRing R
inst✝ : Invertible ↑p
k : ℕ
⊢ (bind₁ (xInTermsOfW p R)) (W_ R k) = X k

Tactic:
rw [wittPolynomial_eq_sum_C_mul_X_pow, map_sum]
  simp only [map_pow, map_mul, algHom_C, algebraMap_eq]
  rw [sum_range_succ_comm, tsub_self, pow_zero, pow_one, bind₁_X_right, mul_comm, ← C_pow,
    xInTermsOfW_aux]
  simp only [C_pow, bind₁_X_right, sub_add_cancel]

Goal state after:
Module: Mathlib.RingTheory.WittVector.StructurePolynomial

Goal state before:
pp: case succ
p : ℕ
idx : Type u_2
hp : Fact (Nat.Prime p)
Φ : MvPolynomial idx ℤ
n k : ℕ
hk : k ≤ n
⊢ (map (Int.castRingHom (ZMod (p ^ (n + 1))))) (↑p ^ k * (expand p) (wittStructureInt p Φ k) ^ p ^ (n - k)) =
    (map (Int.castRingHom (ZMod (p ^ (n + 1))))) (C (↑p ^ k) * wittStructureInt p Φ k ^ p ^ (n + 1 - k))

Tactic:
← sub_eq_zero,

Goal state after:
case succ
p : ℕ
idx : Type u_2
hp : Fact (Nat.Prime p)
Φ : MvPolynomial idx ℤ
n k : ℕ
hk : k ≤ n
⊢ (map (Int.castRingHom (ZMod (p ^ (n + 1))))) (↑p ^ k * (expand p) (wittStructureInt p Φ k) ^ p ^ (n - k)) -
      (map (Int.castRingHom (ZMod (p ^ (n + 1))))) (C (↑p ^ k) * wittStructureInt p Φ k ^ p ^ (n + 1 - k)) =
    0