Theorem: FractionalIdeal.count_well_defined
File: Mathlib/RingTheory/DedekindDomain/Factorization.lean

Proof steps:
state_before: R : Type u_1
inst✝⁴ : CommRing R
K : Type u_2
inst✝³ : Field K
inst✝² : Algebra R K
inst✝¹ : IsFractionRing R K
inst✝ : IsDedekindDomain R
v : HeightOneSpectrum R
I : FractionalIdeal R⁰ K
hI : I ≠ 0
a : R
J : Ideal R
h_aJ : I = spanSingleton R⁰ ((algebraMap R K) a)⁻¹ * ↑J
⊢ count K v I =
    ↑((Associates.mk v.asIdeal).count (Associates.mk J).factors) -
      ↑((Associates.mk v.asIdeal).count (Associates.mk (Ideal.span {a})).factors)
state_after: R : Type u_1
inst✝⁴ : CommRing R
K : Type u_2
inst✝³ : Field K
inst✝² : Algebra R K
inst✝¹ : IsFractionRing R K
inst✝ : IsDedekindDomain R
v : HeightOneSpectrum R
I : FractionalIdeal R⁰ K
hI : I ≠ 0
a : R
J : Ideal R
h_aJ : I = spanSingleton R⁰ ((algebraMap R K) a)⁻¹ * ↑J
a₁ : R := choose ⋯
⊢ count K v I =
    ↑((Associates.mk v.asIdeal).count (Associates.mk J).factors) -
      ↑((Associates.mk v.asIdeal).count (Associates.mk (Ideal.span {a})).factors)
tactic: set a₁ := choose (exists_eq_spanSingleton_mul I)
state_before: R : Type u_1
inst✝⁴ : CommRing R
K : Type u_2
inst✝³ : Field K
inst✝² : Algebra R K
inst✝¹ : IsFractionRing R K
inst✝ : IsDedekindDomain R
v : HeightOneSpectrum R
I : FractionalIdeal R⁰ K
hI : I ≠ 0
a : R
J : Ideal R
h_aJ : I = spanSingleton R⁰ ((algebraMap R K) a)⁻¹ * ↑J
a₁ : R := choose ⋯
⊢ count K v I =
    ↑((Associates.mk v.asIdeal).count (Associates.mk J).factors) -
      ↑((Associates.mk v.asIdeal).count (Associates.mk (Ideal.span {a})).factors)
state_after: R : Type u_1
inst✝⁴ : CommRing R
K : Type u_2
inst✝³ : Field K
inst✝² : Algebra R K
inst✝¹ : IsFractionRing R K
inst✝ : IsDedekindDomain R
v : HeightOneSpectrum R
I : FractionalIdeal R⁰ K
hI : I ≠ 0
a : R
J : Ideal R
h_aJ : I = spanSingleton R⁰ ((algebraMap R K) a)⁻¹ * ↑J
a₁ : R := choose ⋯
J₁ : Ideal R := choose ⋯
⊢ count K v I =
    ↑((Associates.mk v.asIdeal).count (Associates.mk J).factors) -
      ↑((Associates.mk v.asIdeal).count (Associates.mk (Ideal.span {a})).factors)
tactic: set J₁ := choose (choose_spec (exists_eq_spanSingleton_mul I))
state_before: R : Type u_1
inst✝⁴ : CommRing R
K : Type u_2
inst✝³ : Field K
inst✝² : Algebra R K
inst✝¹ : IsFractionRing R K
inst✝ : IsDedekindDomain R
v : HeightOneSpectrum R
I : FractionalIdeal R⁰ K
hI : I ≠ 0
a : R
J : Ideal R
h_aJ : I = spanSingleton R⁰ ((algebraMap R K) a)⁻¹ * ↑J
a₁ : R := choose ⋯
J₁ : Ideal R := choose ⋯
⊢ count K v I =
    ↑((Associates.mk v.asIdeal).count (Associates.mk J).factors) -
      ↑((Associates.mk v.asIdeal).count (Associates.mk (Ideal.span {a})).factors)
state_after: R : Type u_1
inst✝⁴ : CommRing R
K : Type u_2
inst✝³ : Field K
inst✝² : Algebra R K
inst✝¹ : IsFractionRing R K
inst✝ : IsDedekindDomain R
v : HeightOneSpectrum R
I : FractionalIdeal R⁰ K
hI : I ≠ 0
a : R
J : Ideal R
h_aJ : I = spanSingleton R⁰ ((algebraMap R K) a)⁻¹ * ↑J
a₁ : R := choose ⋯
J₁ : Ideal R := choose ⋯
h_a₁J₁ : I = spanSingleton R⁰ ((algebraMap R K) a₁)⁻¹ * ↑J₁
⊢ count K v I =
    ↑((Associates.mk v.asIdeal).count (Associates.mk J).factors) -
      ↑((Associates.mk v.asIdeal).count (Associates.mk (Ideal.span {a})).factors)
tactic: have h_a₁J₁ : I = spanSingleton R⁰ ((algebraMap R K) a₁)⁻¹ * ↑J₁ :=
    (choose_spec (choose_spec (exists_eq_spanSingleton_mul I))).2
state_before: R : Type u_1
inst✝⁴ : CommRing R
K : Type u_2
inst✝³ : Field K
inst✝² : Algebra R K
inst✝¹ : IsFractionRing R K
inst✝ : IsDedekindDomain R
v : HeightOneSpectrum R
I : FractionalIdeal R⁰ K
hI : I ≠ 0
a : R
J : Ideal R
h_aJ : I = spanSingleton R⁰ ((algebraMap R K) a)⁻¹ * ↑J
a₁ : R := choose ⋯
J₁ : Ideal R := choose ⋯
h_a₁J₁ : I = spanSingleton R⁰ ((algebraMap R K) a₁)⁻¹ * ↑J₁
⊢ count K v I =
    ↑((Associates.mk v.asIdeal).count (Associates.mk J).factors) -
      ↑((Associates.mk v.asIdeal).count (Associates.mk (Ideal.span {a})).factors)
state_after: R : Type u_1
inst✝⁴ : CommRing R
K : Type u_2
inst✝³ : Field K
inst✝² : Algebra R K
inst✝¹ : IsFractionRing R K
inst✝ : IsDedekindDomain R
v : HeightOneSpectrum R
I : FractionalIdeal R⁰ K
hI : I ≠ 0
a : R
J : Ideal R
h_aJ : I = spanSingleton R⁰ ((algebraMap R K) a)⁻¹ * ↑J
a₁ : R := choose ⋯
J₁ : Ideal R := choose ⋯
h_a₁J₁ : I = spanSingleton R⁰ ((algebraMap R K) a₁)⁻¹ * ↑J₁
h_a₁_ne_zero : a₁ ≠ 0
⊢ count K v I =
    ↑((Associates.mk v.asIdeal).count (Associates.mk J).factors) -
      ↑((Associates.mk v.asIdeal).count (Associates.mk (Ideal.span {a})).factors)
tactic: have h_a₁_ne_zero : a₁ ≠ 0 := (choose_spec (choose_spec (exists_eq_spanSingleton_mul I))).1
state_before: R : Type u_1
inst✝⁴ : CommRing R
K : Type u_2
inst✝³ : Field K
inst✝² : Algebra R K
inst✝¹ : IsFractionRing R K
inst✝ : IsDedekindDomain R
v : HeightOneSpectrum R
I : FractionalIdeal R⁰ K
hI : I ≠ 0
a : R
J : Ideal R
h_aJ : I = spanSingleton R⁰ ((algebraMap R K) a)⁻¹ * ↑J
a₁ : R := choose ⋯
J₁ : Ideal R := choose ⋯
h_a₁J₁ : I = spanSingleton R⁰ ((algebraMap R K) a₁)⁻¹ * ↑J₁
h_a₁_ne_zero : a₁ ≠ 0
⊢ count K v I =
    ↑((Associates.mk v.asIdeal).count (Associates.mk J).factors) -
      ↑((Associates.mk v.asIdeal).count (Associates.mk (Ideal.span {a})).factors)
state_after: R : Type u_1
inst✝⁴ : CommRing R
K : Type u_2
inst✝³ : Field K
inst✝² : Algebra R K
inst✝¹ : IsFractionRing R K
inst✝ : IsDedekindDomain R
v : HeightOneSpectrum R
I : FractionalIdeal R⁰ K
hI : I ≠ 0
a : R
J : Ideal R
h_aJ : I = spanSingleton R⁰ ((algebraMap R K) a)⁻¹ * ↑J
a₁ : R := choose ⋯
J₁ : Ideal R := choose ⋯
h_a₁J₁ : I = spanSingleton R⁰ ((algebraMap R K) a₁)⁻¹ * ↑J₁
h_a₁_ne_zero : a₁ ≠ 0
h_J₁_ne_zero : J₁ ≠ 0
⊢ count K v I =
    ↑((Associates.mk v.asIdeal).count (Associates.mk J).factors) -
      ↑((Associates.mk v.asIdeal).count (Associates.mk (Ideal.span {a})).factors)
tactic: have h_J₁_ne_zero : J₁ ≠ 0 := ideal_factor_ne_zero hI h_a₁J₁
state_before: R : Type u_1
inst✝⁴ : CommRing R
K : Type u_2
inst✝³ : Field K
inst✝² : Algebra R K
inst✝¹ : IsFractionRing R K
inst✝ : IsDedekindDomain R
v : HeightOneSpectrum R
I : FractionalIdeal R⁰ K
hI : I ≠ 0
a : R
J : Ideal R
h_aJ : I = spanSingleton R⁰ ((algebraMap R K) a)⁻¹ * ↑J
a₁ : R := choose ⋯
J₁ : Ideal R := choose ⋯
h_a₁J₁ : I = spanSingleton R⁰ ((algebraMap R K) a₁)⁻¹ * ↑J₁
h_a₁_ne_zero : a₁ ≠ 0
h_J₁_ne_zero : J₁ ≠ 0
⊢ count K v I =
    ↑((Associates.mk v.asIdeal).count (Associates.mk J).factors) -
      ↑((Associates.mk v.asIdeal).count (Associates.mk (Ideal.span {a})).factors)
state_after: R : Type u_1
inst✝⁴ : CommRing R
K : Type u_2
inst✝³ : Field K
inst✝² : Algebra R K
inst✝¹ : IsFractionRing R K
inst✝ : IsDedekindDomain R
v : HeightOneSpectrum R
I : FractionalIdeal R⁰ K
hI : I ≠ 0
a : R
J : Ideal R
h_aJ : I = spanSingleton R⁰ ((algebraMap R K) a)⁻¹ * ↑J
a₁ : R := choose ⋯
J₁ : Ideal R := choose ⋯
h_a₁J₁ : I = spanSingleton R⁰ ((algebraMap R K) a₁)⁻¹ * ↑J₁
h_a₁_ne_zero : a₁ ≠ 0
h_J₁_ne_zero : J₁ ≠ 0
h_a_ne_zero : Ideal.span {a} ≠ 0
⊢ count K v I =
    ↑((Associates.mk v.asIdeal).count (Associates.mk J).factors) -
      ↑((Associates.mk v.asIdeal).count (Associates.mk (Ideal.span {a})).factors)
tactic: have h_a_ne_zero : Ideal.span {a} ≠ 0 := constant_factor_ne_zero hI h_aJ
state_before: R : Type u_1
inst✝⁴ : CommRing R
K : Type u_2
inst✝³ : Field K
inst✝² : Algebra R K
inst✝¹ : IsFractionRing R K
inst✝ : IsDedekindDomain R
v : HeightOneSpectrum R
I : FractionalIdeal R⁰ K
hI : I ≠ 0
a : R
J : Ideal R
h_aJ : I = spanSingleton R⁰ ((algebraMap R K) a)⁻¹ * ↑J
a₁ : R := choose ⋯
J₁ : Ideal R := choose ⋯
h_a₁J₁ : I = spanSingleton R⁰ ((algebraMap R K) a₁)⁻¹ * ↑J₁
h_a₁_ne_zero : a₁ ≠ 0
h_J₁_ne_zero : J₁ ≠ 0
h_a_ne_zero : Ideal.span {a} ≠ 0
⊢ count K v I =
    ↑((Associates.mk v.asIdeal).count (Associates.mk J).factors) -
      ↑((Associates.mk v.asIdeal).count (Associates.mk (Ideal.span {a})).factors)
state_after: R : Type u_1
inst✝⁴ : CommRing R
K : Type u_2
inst✝³ : Field K
inst✝² : Algebra R K
inst✝¹ : IsFractionRing R K
inst✝ : IsDedekindDomain R
v : HeightOneSpectrum R
I : FractionalIdeal R⁰ K
hI : I ≠ 0
a : R
J : Ideal R
h_aJ : I = spanSingleton R⁰ ((algebraMap R K) a)⁻¹ * ↑J
a₁ : R := choose ⋯
J₁ : Ideal R := choose ⋯
h_a₁J₁ : I = spanSingleton R⁰ ((algebraMap R K) a₁)⁻¹ * ↑J₁
h_a₁_ne_zero : a₁ ≠ 0
h_J₁_ne_zero : J₁ ≠ 0
h_a_ne_zero : Ideal.span {a} ≠ 0
h_J_ne_zero : J ≠ 0
⊢ count K v I =
    ↑((Associates.mk v.asIdeal).count (Associates.mk J).factors) -
      ↑((Associates.mk v.asIdeal).count (Associates.mk (Ideal.span {a})).factors)
tactic: have h_J_ne_zero : J ≠ 0 := ideal_factor_ne_zero hI h_aJ
state_before: R : Type u_1
inst✝⁴ : CommRing R
K : Type u_2
inst✝³ : Field K
inst✝² : Algebra R K
inst✝¹ : IsFractionRing R K
inst✝ : IsDedekindDomain R
v : HeightOneSpectrum R
I : FractionalIdeal R⁰ K
hI : I ≠ 0
a : R
J : Ideal R
h_aJ : I = spanSingleton R⁰ ((algebraMap R K) a)⁻¹ * ↑J
a₁ : R := choose ⋯
J₁ : Ideal R := choose ⋯
h_a₁J₁ : I = spanSingleton R⁰ ((algebraMap R K) a₁)⁻¹ * ↑J₁
h_a₁_ne_zero : a₁ ≠ 0
h_J₁_ne_zero : J₁ ≠ 0
h_a_ne_zero : Ideal.span {a} ≠ 0
h_J_ne_zero : J ≠ 0
⊢ count K v I =
    ↑((Associates.mk v.asIdeal).count (Associates.mk J).factors) -
      ↑((Associates.mk v.asIdeal).count (Associates.mk (Ideal.span {a})).factors)
state_after: R : Type u_1
inst✝⁴ : CommRing R
K : Type u_2
inst✝³ : Field K
inst✝² : Algebra R K
inst✝¹ : IsFractionRing R K
inst✝ : IsDedekindDomain R
v : HeightOneSpectrum R
I : FractionalIdeal R⁰ K
hI : I ≠ 0
a : R
J : Ideal R
h_aJ : I = spanSingleton R⁰ ((algebraMap R K) a)⁻¹ * ↑J
a₁ : R := choose ⋯
J₁ : Ideal R := choose ⋯
h_a₁J₁ : I = spanSingleton R⁰ ((algebraMap R K) a₁)⁻¹ * ↑J₁
h_a₁_ne_zero : a₁ ≠ 0
h_J₁_ne_zero : J₁ ≠ 0
h_a_ne_zero : Ideal.span {a} ≠ 0
h_J_ne_zero : J ≠ 0
h_a₁' : spanSingleton R⁰ ((algebraMap R K) a₁) ≠ 0
⊢ count K v I =
    ↑((Associates.mk v.asIdeal).count (Associates.mk J).factors) -
      ↑((Associates.mk v.asIdeal).count (Associates.mk (Ideal.span {a})).factors)
tactic: have h_a₁' : spanSingleton R⁰ ((algebraMap R K) a₁) ≠ 0 := by
    rw [ne_eq, spanSingleton_eq_zero_iff, ← (algebraMap R K).map_zero,
      Injective.eq_iff (IsLocalization.injective K (le_refl R⁰))]
    exact h_a₁_ne_zero
state_before: R : Type u_1
inst✝⁴ : CommRing R
K : Type u_2
inst✝³ : Field K
inst✝² : Algebra R K
inst✝¹ : IsFractionRing R K
inst✝ : IsDedekindDomain R
v : HeightOneSpectrum R
I : FractionalIdeal R⁰ K
hI : I ≠ 0
a : R
J : Ideal R
h_aJ : I = spanSingleton R⁰ ((algebraMap R K) a)⁻¹ * ↑J
a₁ : R := choose ⋯
J₁ : Ideal R := choose ⋯
h_a₁J₁ : I = spanSingleton R⁰ ((algebraMap R K) a₁)⁻¹ * ↑J₁
h_a₁_ne_zero : a₁ ≠ 0
h_J₁_ne_zero : J₁ ≠ 0
h_a_ne_zero : Ideal.span {a} ≠ 0
h_J_ne_zero : J ≠ 0
h_a₁' : spanSingleton R⁰ ((algebraMap R K) a₁) ≠ 0
⊢ count K v I =
    ↑((Associates.mk v.asIdeal).count (Associates.mk J).factors) -
      ↑((Associates.mk v.asIdeal).count (Associates.mk (Ideal.span {a})).factors)
state_after: R : Type u_1
inst✝⁴ : CommRing R
K : Type u_2
inst✝³ : Field K
inst✝² : Algebra R K
inst✝¹ : IsFractionRing R K
inst✝ : IsDedekindDomain R
v : HeightOneSpectrum R
I : FractionalIdeal R⁰ K
hI : I ≠ 0
a : R
J : Ideal R
h_aJ : I = spanSingleton R⁰ ((algebraMap R K) a)⁻¹ * ↑J
a₁ : R := choose ⋯
J₁ : Ideal R := choose ⋯
h_a₁J₁ : I = spanSingleton R⁰ ((algebraMap R K) a₁)⁻¹ * ↑J₁
h_a₁_ne_zero : a₁ ≠ 0
h_J₁_ne_zero : J₁ ≠ 0
h_a_ne_zero : Ideal.span {a} ≠ 0
h_J_ne_zero : J ≠ 0
h_a₁' : spanSingleton R⁰ ((algebraMap R K) a₁) ≠ 0
h_a' : spanSingleton R⁰ ((algebraMap R K) a) ≠ 0
⊢ count K v I =
    ↑((Associates.mk v.asIdeal).count (Associates.mk J).factors) -
      ↑((Associates.mk v.asIdeal).count (Associates.mk (Ideal.span {a})).factors)
tactic: have h_a' : spanSingleton R⁰ ((algebraMap R K) a) ≠ 0 := by
    rw [ne_eq, spanSingleton_eq_zero_iff, ← (algebraMap R K).map_zero,
      Injective.eq_iff (IsLocalization.injective K (le_refl R⁰))]
    rw [ne_eq, Ideal.zero_eq_bot, Ideal.span_singleton_eq_bot] at h_a_ne_zero
    exact h_a_ne_zero
state_before: R : Type u_1
inst✝⁴ : CommRing R
K : Type u_2
inst✝³ : Field K
inst✝² : Algebra R K
inst✝¹ : IsFractionRing R K
inst✝ : IsDedekindDomain R
v : HeightOneSpectrum R
I : FractionalIdeal R⁰ K
hI : I ≠ 0
a : R
J : Ideal R
h_aJ : I = spanSingleton R⁰ ((algebraMap R K) a)⁻¹ * ↑J
a₁ : R := choose ⋯
J₁ : Ideal R := choose ⋯
h_a₁J₁ : I = spanSingleton R⁰ ((algebraMap R K) a₁)⁻¹ * ↑J₁
h_a₁_ne_zero : a₁ ≠ 0
h_J₁_ne_zero : J₁ ≠ 0
h_a_ne_zero : Ideal.span {a} ≠ 0
h_J_ne_zero : J ≠ 0
h_a₁' : spanSingleton R⁰ ((algebraMap R K) a₁) ≠ 0
h_a' : spanSingleton R⁰ ((algebraMap R K) a) ≠ 0
⊢ count K v I =
    ↑((Associates.mk v.asIdeal).count (Associates.mk J).factors) -
      ↑((Associates.mk v.asIdeal).count (Associates.mk (Ideal.span {a})).factors)
state_after: R : Type u_1
inst✝⁴ : CommRing R
K : Type u_2
inst✝³ : Field K
inst✝² : Algebra R K
inst✝¹ : IsFractionRing R K
inst✝ : IsDedekindDomain R
v : HeightOneSpectrum R
I : FractionalIdeal R⁰ K
hI : I ≠ 0
a : R
J : Ideal R
h_aJ : I = spanSingleton R⁰ ((algebraMap R K) a)⁻¹ * ↑J
a₁ : R := choose ⋯
J₁ : Ideal R := choose ⋯
h_a₁J₁ : I = spanSingleton R⁰ ((algebraMap R K) a₁)⁻¹ * ↑J₁
h_a₁_ne_zero : a₁ ≠ 0
h_J₁_ne_zero : J₁ ≠ 0
h_a_ne_zero : Ideal.span {a} ≠ 0
h_J_ne_zero : J ≠ 0
h_a₁' : spanSingleton R⁰ ((algebraMap R K) a₁) ≠ 0
h_a' : spanSingleton R⁰ ((algebraMap R K) a) ≠ 0
hv : Irreducible (Associates.mk v.asIdeal)
⊢ count K v I =
    ↑((Associates.mk v.asIdeal).count (Associates.mk J).factors) -
      ↑((Associates.mk v.asIdeal).count (Associates.mk (Ideal.span {a})).factors)
tactic: have hv : Irreducible (Associates.mk v.asIdeal) := by
    exact Associates.irreducible_mk.mpr v.irreducible
state_before: R : Type u_1
inst✝⁴ : CommRing R
K : Type u_2
inst✝³ : Field K
inst✝² : Algebra R K
inst✝¹ : IsFractionRing R K
inst✝ : IsDedekindDomain R
v : HeightOneSpectrum R
I : FractionalIdeal R⁰ K
hI : I ≠ 0
a : R
J : Ideal R
h_aJ : I = spanSingleton R⁰ ((algebraMap R K) a)⁻¹ * ↑J
a₁ : R := choose ⋯
J₁ : Ideal R := choose ⋯
h_a₁J₁ : I = spanSingleton R⁰ ((algebraMap R K) a₁)⁻¹ * ↑J₁
h_a₁_ne_zero : a₁ ≠ 0
h_J₁_ne_zero : J₁ ≠ 0
h_a_ne_zero : Ideal.span {a} ≠ 0
h_J_ne_zero : J ≠ 0
h_a₁' : spanSingleton R⁰ ((algebraMap R K) a₁) ≠ 0
h_a' : spanSingleton R⁰ ((algebraMap R K) a) ≠ 0
hv : Irreducible (Associates.mk v.asIdeal)
⊢ count K v I =
    ↑((Associates.mk v.asIdeal).count (Associates.mk J).factors) -
      ↑((Associates.mk v.asIdeal).count (Associates.mk (Ideal.span {a})).factors)
state_after: R : Type u_1
inst✝⁴ : CommRing R
K : Type u_2
inst✝³ : Field K
inst✝² : Algebra R K
inst✝¹ : IsFractionRing R K
inst✝ : IsDedekindDomain R
v : HeightOneSpectrum R
I : FractionalIdeal R⁰ K
hI : I ≠ 0
a : R
J : Ideal R
a₁ : R := choose ⋯
J₁ : Ideal R := choose ⋯
h_aJ : ↑(J₁ * Ideal.span {a}) = ↑(J * Ideal.span {a₁})
h_a₁J₁ : I = spanSingleton R⁰ ((algebraMap R K) a₁)⁻¹ * ↑J₁
h_a₁_ne_zero : a₁ ≠ 0
h_J₁_ne_zero : J₁ ≠ 0
h_a_ne_zero : Ideal.span {a} ≠ 0
h_J_ne_zero : J ≠ 0
h_a₁' : spanSingleton R⁰ ((algebraMap R K) a₁) ≠ 0
h_a' : spanSingleton R⁰ ((algebraMap R K) a) ≠ 0
hv : Irreducible (Associates.mk v.asIdeal)
⊢ count K v I =
    ↑((Associates.mk v.asIdeal).count (Associates.mk J).factors) -
      ↑((Associates.mk v.asIdeal).count (Associates.mk (Ideal.span {a})).factors)
tactic: rw [h_a₁J₁, ← div_spanSingleton, ← div_spanSingleton, div_eq_div_iff h_a₁' h_a',
    ← coeIdeal_span_singleton, ← coeIdeal_span_singleton, ← coeIdeal_mul, ← coeIdeal_mul] at h_aJ
state_before: R : Type u_1
inst✝⁴ : CommRing R
K : Type u_2
inst✝³ : Field K
inst✝² : Algebra R K
inst✝¹ : IsFractionRing R K
inst✝ : IsDedekindDomain R
v : HeightOneSpectrum R
I : FractionalIdeal R⁰ K
hI : I ≠ 0
a : R
J : Ideal R
a₁ : R := choose ⋯
J₁ : Ideal R := choose ⋯
h_aJ : ↑(J₁ * Ideal.span {a}) = ↑(J * Ideal.span {a₁})
h_a₁J₁ : I = spanSingleton R⁰ ((algebraMap R K) a₁)⁻¹ * ↑J₁
h_a₁_ne_zero : a₁ ≠ 0
h_J₁_ne_zero : J₁ ≠ 0
h_a_ne_zero : Ideal.span {a} ≠ 0
h_J_ne_zero : J ≠ 0
h_a₁' : spanSingleton R⁰ ((algebraMap R K) a₁) ≠ 0
h_a' : spanSingleton R⁰ ((algebraMap R K) a) ≠ 0
hv : Irreducible (Associates.mk v.asIdeal)
⊢ count K v I =
    ↑((Associates.mk v.asIdeal).count (Associates.mk J).factors) -
      ↑((Associates.mk v.asIdeal).count (Associates.mk (Ideal.span {a})).factors)
state_after: R : Type u_1
inst✝⁴ : CommRing R
K : Type u_2
inst✝³ : Field K
inst✝² : Algebra R K
inst✝¹ : IsFractionRing R K
inst✝ : IsDedekindDomain R
v : HeightOneSpectrum R
I : FractionalIdeal R⁰ K
hI : I ≠ 0
a : R
J : Ideal R
a₁ : R := choose ⋯
J₁ : Ideal R := choose ⋯
h_aJ : ↑(J₁ * Ideal.span {a}) = ↑(J * Ideal.span {a₁})
h_a₁J₁ : I = spanSingleton R⁰ ((algebraMap R K) a₁)⁻¹ * ↑J₁
h_a₁_ne_zero : a₁ ≠ 0
h_J₁_ne_zero : J₁ ≠ 0
h_a_ne_zero : Ideal.span {a} ≠ 0
h_J_ne_zero : J ≠ 0
h_a₁' : spanSingleton R⁰ ((algebraMap R K) a₁) ≠ 0
h_a' : spanSingleton R⁰ ((algebraMap R K) a) ≠ 0
hv : Irreducible (Associates.mk v.asIdeal)
⊢ Associates.mk J ≠ 0

R : Type u_1
inst✝⁴ : CommRing R
K : Type u_2
inst✝³ : Field K
inst✝² : Algebra R K
inst✝¹ : IsFractionRing R K
inst✝ : IsDedekindDomain R
v : HeightOneSpectrum R
I : FractionalIdeal R⁰ K
hI : I ≠ 0
a : R
J : Ideal R
a₁ : R := choose ⋯
J₁ : Ideal R := choose ⋯
h_aJ : ↑(J₁ * Ideal.span {a}) = ↑(J * Ideal.span {a₁})
h_a₁J₁ : I = spanSingleton R⁰ ((algebraMap R K) a₁)⁻¹ * ↑J₁
h_a₁_ne_zero : a₁ ≠ 0
h_J₁_ne_zero : J₁ ≠ 0
h_a_ne_zero : Ideal.span {a} ≠ 0
h_J_ne_zero : J ≠ 0
h_a₁' : spanSingleton R⁰ ((algebraMap R K) a₁) ≠ 0
h_a' : spanSingleton R⁰ ((algebraMap R K) a) ≠ 0
hv : Irreducible (Associates.mk v.asIdeal)
⊢ Associates.mk (Ideal.span {choose ⋯}) ≠ 0

R : Type u_1
inst✝⁴ : CommRing R
K : Type u_2
inst✝³ : Field K
inst✝² : Algebra R K
inst✝¹ : IsFractionRing R K
inst✝ : IsDedekindDomain R
v : HeightOneSpectrum R
I : FractionalIdeal R⁰ K
hI : I ≠ 0
a : R
J : Ideal R
a₁ : R := choose ⋯
J₁ : Ideal R := choose ⋯
h_aJ : ↑(J₁ * Ideal.span {a}) = ↑(J * Ideal.span {a₁})
h_a₁J₁ : I = spanSingleton R⁰ ((algebraMap R K) a₁)⁻¹ * ↑J₁
h_a₁_ne_zero : a₁ ≠ 0
h_J₁_ne_zero : J₁ ≠ 0
h_a_ne_zero : Ideal.span {a} ≠ 0
h_J_ne_zero : J ≠ 0
h_a₁' : spanSingleton R⁰ ((algebraMap R K) a₁) ≠ 0
h_a' : spanSingleton R⁰ ((algebraMap R K) a) ≠ 0
hv : Irreducible (Associates.mk v.asIdeal)
⊢ Associates.mk (choose ⋯) ≠ 0

R : Type u_1
inst✝⁴ : CommRing R
K : Type u_2
inst✝³ : Field K
inst✝² : Algebra R K
inst✝¹ : IsFractionRing R K
inst✝ : IsDedekindDomain R
v : HeightOneSpectrum R
I : FractionalIdeal R⁰ K
hI : I ≠ 0
a : R
J : Ideal R
a₁ : R := choose ⋯
J₁ : Ideal R := choose ⋯
h_aJ : ↑(J₁ * Ideal.span {a}) = ↑(J * Ideal.span {a₁})
h_a₁J₁ : I = spanSingleton R⁰ ((algebraMap R K) a₁)⁻¹ * ↑J₁
h_a₁_ne_zero : a₁ ≠ 0
h_J₁_ne_zero : J₁ ≠ 0
h_a_ne_zero : Ideal.span {a} ≠ 0
h_J_ne_zero : J ≠ 0
h_a₁' : spanSingleton R⁰ ((algebraMap R K) a₁) ≠ 0
h_a' : spanSingleton R⁰ ((algebraMap R K) a) ≠ 0
hv : Irreducible (Associates.mk v.asIdeal)
⊢ Associates.mk (Ideal.span {a}) ≠ 0
tactic: rw [count, dif_neg hI, sub_eq_sub_iff_add_eq_add, ← ofNat_add, ← ofNat_add, natCast_inj,
    ← Associates.count_mul _ _ hv, ← Associates.count_mul _ _ hv, Associates.mk_mul_mk,
    Associates.mk_mul_mk, coeIdeal_injective h_aJ]