l3lab/ntp-mathlib huggingface dataset:
/-- Strengthening of `IsLocalization.exist_integer_multiples`:
Let `J ≠ ⊤` be an ideal in a Dedekind domain `A`, and `f ≠ 0` a finite collection
of elements of `K = Frac(A)`, then we can multiply the elements of `f` by some `a : K`
to find a collection of elements of `A` that is not completely contained in `J`. -/
theorem Ideal.exist_integer_multiples_not_mem {J : Ideal A} (hJ : J ≠ ⊤) {ι : Type*} (s : Finset ι)
    (f : ι → K) {j} (hjs : j ∈ s) (hjf : f j ≠ 0) :
    ∃ a : K,
      (∀ i ∈ s, IsLocalization.IsInteger A (a * f i)) ∧
        ∃ i ∈ s, a * f i ∉ (J : FractionalIdeal A⁰ K) := by
  -- Consider the fractional ideal `I` spanned by the `f`s.
  let I : FractionalIdeal A⁰ K := spanFinset A s f
  have hI0 : I ≠ 0 := spanFinset_ne_zero.mpr ⟨j, hjs, hjf⟩
  -- We claim the multiplier `a` we're looking for is in `I⁻¹ \ (J / I)`.
  suffices ↑J / I < I⁻¹ by
    obtain ⟨_, a, hI, hpI⟩ := SetLike.lt_iff_le_and_exists.mp this
    rw [mem_inv_iff hI0] at hI
    refine' ⟨a, fun i hi => _, _⟩
    -- By definition, `a ∈ I⁻¹` multiplies elements of `I` into elements of `1`,
    -- in other words, `a * f i` is an integer.
    · exact (mem_one_iff _).mp (hI (f i) (Submodule.subset_span (Set.mem_image_of_mem f hi)))
    · contrapose! hpI
      -- And if all `a`-multiples of `I` are an element of `J`,
      -- then `a` is actually an element of `J / I`, contradiction.
      refine' (mem_div_iff_of_nonzero hI0).mpr fun y hy => Submodule.span_induction hy _ _ _ _
      · rintro _ ⟨i, hi, rfl⟩; exact hpI i hi
      · rw [mul_zero]; exact Submodule.zero_mem _
      · intro x y hx hy; rw [mul_add]; exact Submodule.add_mem _ hx hy
      · 

Proof state:
case intro.intro.intro.refine'_2.refine'_4
R : Type u_1
A : Type u_2
K : Type u_3
inst✝⁶ : CommRing R
inst✝⁵ : CommRing A
inst✝⁴ : Field K
inst✝³ : IsDomain A
inst✝² : IsDedekindDomain A
inst✝¹ : Algebra A K
inst✝ : IsFractionRing A K
J : Ideal A
hJ : J ≠ ⊤
ι : Type u_4
s : Finset ι
f : ι → K
j : ι
hjs : j ∈ s
hjf : f j ≠ 0
I : FractionalIdeal A⁰ K := spanFinset A s f
hI0 : I ≠ 0
this : ↑J / I < I⁻¹
left✝ : ↑J / I ≤ I⁻¹
a : K
hI : ∀ y ∈ I, a * y ∈ 1
hpI : ∀ i ∈ s, a * f i ∈ ↑J
y : K
hy : y ∈ I
⊢ ∀ (a_1 : A) (x : K), a * x ∈ ↑J → a * a_1 • x ∈ ↑J

Next tactic:
intro b x hx
/-- Strengthening of `IsLocalization.exist_integer_multiples`:
Let `J ≠ ⊤` be an ideal in a Dedekind domain `A`, and `f ≠ 0` a finite collection
of elements of `K = Frac(A)`, then we can multiply the elements of `f` by some `a : K`
to find a collection of elements of `A` that is not completely contained in `J`. -/
theorem Ideal.exist_integer_multiples_not_mem {J : Ideal A} (hJ : J ≠ ⊤) {ι : Type*} (s : Finset ι)
    (f : ι → K) {j} (hjs : j ∈ s) (hjf : f j ≠ 0) :
    ∃ a : K,
      (∀ i ∈ s, IsLocalization.IsInteger A (a * f i)) ∧
        ∃ i ∈ s, a * f i ∉ (J : FractionalIdeal A⁰ K) := by
  -- Consider the fractional ideal `I` spanned by the `f`s.
  let I : FractionalIdeal A⁰ K := spanFinset A s f
  have hI0 : I ≠ 0 := spanFinset_ne_zero.mpr ⟨j, hjs, hjf⟩
  -- We claim the multiplier `a` we're looking for is in `I⁻¹ \ (J / I)`.
  suffices ↑J / I < I⁻¹ by
    obtain ⟨_, a, hI, hpI⟩ := SetLike.lt_iff_le_and_exists.mp this
    rw [mem_inv_iff hI0] at hI
    refine' ⟨a, fun i hi => _, _⟩
    -- By definition, `a ∈ I⁻¹` multiplies elements of `I` into elements of `1`,
    -- in other words, `a * f i` is an integer.
    · exact (mem_one_iff _).mp (hI (f i) (Submodule.subset_span (Set.mem_image_of_mem f hi)))
    · contrapose! hpI
      -- And if all `a`-multiples of `I` are an element of `J`,
      -- then `a` is actually an element of `J / I`, contradiction.
      refine' (mem_div_iff_of_nonzero hI0).mpr fun y hy => Submodule.span_induction hy _ _ _ _
      · rintro _ ⟨i, hi, rfl⟩; exact hpI i hi
      · rw [mul_zero]; exact Submodule.zero_mem _
      · intro x y hx hy; rw [mul_add]; exact Submodule.add_mem _ hx hy
      · intro b x hx; 

Proof state:
case intro.intro.intro.refine'_2.refine'_4
R : Type u_1
A : Type u_2
K : Type u_3
inst✝⁶ : CommRing R
inst✝⁵ : CommRing A
inst✝⁴ : Field K
inst✝³ : IsDomain A
inst✝² : IsDedekindDomain A
inst✝¹ : Algebra A K
inst✝ : IsFractionRing A K
J : Ideal A
hJ : J ≠ ⊤
ι : Type u_4
s : Finset ι
f : ι → K
j : ι
hjs : j ∈ s
hjf : f j ≠ 0
I : FractionalIdeal A⁰ K := spanFinset A s f
hI0 : I ≠ 0
this : ↑J / I < I⁻¹
left✝ : ↑J / I ≤ I⁻¹
a : K
hI : ∀ y ∈ I, a * y ∈ 1
hpI : ∀ i ∈ s, a * f i ∈ ↑J
y : K
hy : y ∈ I
b : A
x : K
hx : a * x ∈ ↑J
⊢ a * b • x ∈ ↑J

Next tactic:
rw [mul_smul_comm]
/-- Strengthening of `IsLocalization.exist_integer_multiples`:
Let `J ≠ ⊤` be an ideal in a Dedekind domain `A`, and `f ≠ 0` a finite collection
of elements of `K = Frac(A)`, then we can multiply the elements of `f` by some `a : K`
to find a collection of elements of `A` that is not completely contained in `J`. -/
theorem Ideal.exist_integer_multiples_not_mem {J : Ideal A} (hJ : J ≠ ⊤) {ι : Type*} (s : Finset ι)
    (f : ι → K) {j} (hjs : j ∈ s) (hjf : f j ≠ 0) :
    ∃ a : K,
      (∀ i ∈ s, IsLocalization.IsInteger A (a * f i)) ∧
        ∃ i ∈ s, a * f i ∉ (J : FractionalIdeal A⁰ K) := by
  -- Consider the fractional ideal `I` spanned by the `f`s.
  let I : FractionalIdeal A⁰ K := spanFinset A s f
  have hI0 : I ≠ 0 := spanFinset_ne_zero.mpr ⟨j, hjs, hjf⟩
  -- We claim the multiplier `a` we're looking for is in `I⁻¹ \ (J / I)`.
  suffices ↑J / I < I⁻¹ by
    obtain ⟨_, a, hI, hpI⟩ := SetLike.lt_iff_le_and_exists.mp this
    rw [mem_inv_iff hI0] at hI
    refine' ⟨a, fun i hi => _, _⟩
    -- By definition, `a ∈ I⁻¹` multiplies elements of `I` into elements of `1`,
    -- in other words, `a * f i` is an integer.
    · exact (mem_one_iff _).mp (hI (f i) (Submodule.subset_span (Set.mem_image_of_mem f hi)))
    · contrapose! hpI
      -- And if all `a`-multiples of `I` are an element of `J`,
      -- then `a` is actually an element of `J / I`, contradiction.
      refine' (mem_div_iff_of_nonzero hI0).mpr fun y hy => Submodule.span_induction hy _ _ _ _
      · rintro _ ⟨i, hi, rfl⟩; exact hpI i hi
      · rw [mul_zero]; exact Submodule.zero_mem _
      · intro x y hx hy; rw [mul_add]; exact Submodule.add_mem _ hx hy
      · intro b x hx; rw [mul_smul_comm]; 

Proof state:
case intro.intro.intro.refine'_2.refine'_4
R : Type u_1
A : Type u_2
K : Type u_3
inst✝⁶ : CommRing R
inst✝⁵ : CommRing A
inst✝⁴ : Field K
inst✝³ : IsDomain A
inst✝² : IsDedekindDomain A
inst✝¹ : Algebra A K
inst✝ : IsFractionRing A K
J : Ideal A
hJ : J ≠ ⊤
ι : Type u_4
s : Finset ι
f : ι → K
j : ι
hjs : j ∈ s
hjf : f j ≠ 0
I : FractionalIdeal A⁰ K := spanFinset A s f
hI0 : I ≠ 0
this : ↑J / I < I⁻¹
left✝ : ↑J / I ≤ I⁻¹
a : K
hI : ∀ y ∈ I, a * y ∈ 1
hpI : ∀ i ∈ s, a * f i ∈ ↑J
y : K
hy : y ∈ I
b : A
x : K
hx : a * x ∈ ↑J
⊢ b • (a * x) ∈ ↑J

Next tactic:
exact Submodule.smul_mem _ b hx
/-- Strengthening of `IsLocalization.exist_integer_multiples`:
Let `J ≠ ⊤` be an ideal in a Dedekind domain `A`, and `f ≠ 0` a finite collection
of elements of `K = Frac(A)`, then we can multiply the elements of `f` by some `a : K`
to find a collection of elements of `A` that is not completely contained in `J`. -/
theorem Ideal.exist_integer_multiples_not_mem {J : Ideal A} (hJ : J ≠ ⊤) {ι : Type*} (s : Finset ι)
    (f : ι → K) {j} (hjs : j ∈ s) (hjf : f j ≠ 0) :
    ∃ a : K,
      (∀ i ∈ s, IsLocalization.IsInteger A (a * f i)) ∧
        ∃ i ∈ s, a * f i ∉ (J : FractionalIdeal A⁰ K) := by
  -- Consider the fractional ideal `I` spanned by the `f`s.
  let I : FractionalIdeal A⁰ K := spanFinset A s f
  have hI0 : I ≠ 0 := spanFinset_ne_zero.mpr ⟨j, hjs, hjf⟩
  -- We claim the multiplier `a` we're looking for is in `I⁻¹ \ (J / I)`.
  suffices ↑J / I < I⁻¹ by
    obtain ⟨_, a, hI, hpI⟩ := SetLike.lt_iff_le_and_exists.mp this
    rw [mem_inv_iff hI0] at hI
    refine' ⟨a, fun i hi => _, _⟩
    -- By definition, `a ∈ I⁻¹` multiplies elements of `I` into elements of `1`,
    -- in other words, `a * f i` is an integer.
    · exact (mem_one_iff _).mp (hI (f i) (Submodule.subset_span (Set.mem_image_of_mem f hi)))
    · contrapose! hpI
      -- And if all `a`-multiples of `I` are an element of `J`,
      -- then `a` is actually an element of `J / I`, contradiction.
      refine' (mem_div_iff_of_nonzero hI0).mpr fun y hy => Submodule.span_induction hy _ _ _ _
      · rintro _ ⟨i, hi, rfl⟩; exact hpI i hi
      · rw [mul_zero]; exact Submodule.zero_mem _
      · intro x y hx hy; rw [mul_add]; exact Submodule.add_mem _ hx hy
      · intro b x hx; rw [mul_smul_comm]; exact Submodule.smul_mem _ b hx
  -- To show the inclusion of `J / I` into `I⁻¹ = 1 / I`, note that `J < I`.
  

Proof state:
R : Type u_1
A : Type u_2
K : Type u_3
inst✝⁶ : CommRing R
inst✝⁵ : CommRing A
inst✝⁴ : Field K
inst✝³ : IsDomain A
inst✝² : IsDedekindDomain A
inst✝¹ : Algebra A K
inst✝ : IsFractionRing A K
J : Ideal A
hJ : J ≠ ⊤
ι : Type u_4
s : Finset ι
f : ι → K
j : ι
hjs : j ∈ s
hjf : f j ≠ 0
I : FractionalIdeal A⁰ K := spanFinset A s f
hI0 : I ≠ 0
⊢ ↑J / I < I⁻¹

Next tactic:
calc
    ↑J / I = ↑J * I⁻¹ := div_eq_mul_inv (↑J) I
    _ < 1 * I⁻¹ := (mul_right_strictMono (inv_ne_zero hI0) ?_)
    _ = I⁻¹ := one_mul _
/-- Strengthening of `IsLocalization.exist_integer_multiples`:
Let `J ≠ ⊤` be an ideal in a Dedekind domain `A`, and `f ≠ 0` a finite collection
of elements of `K = Frac(A)`, then we can multiply the elements of `f` by some `a : K`
to find a collection of elements of `A` that is not completely contained in `J`. -/
theorem Ideal.exist_integer_multiples_not_mem {J : Ideal A} (hJ : J ≠ ⊤) {ι : Type*} (s : Finset ι)
    (f : ι → K) {j} (hjs : j ∈ s) (hjf : f j ≠ 0) :
    ∃ a : K,
      (∀ i ∈ s, IsLocalization.IsInteger A (a * f i)) ∧
        ∃ i ∈ s, a * f i ∉ (J : FractionalIdeal A⁰ K) := by
  -- Consider the fractional ideal `I` spanned by the `f`s.
  let I : FractionalIdeal A⁰ K := spanFinset A s f
  have hI0 : I ≠ 0 := spanFinset_ne_zero.mpr ⟨j, hjs, hjf⟩
  -- We claim the multiplier `a` we're looking for is in `I⁻¹ \ (J / I)`.
  suffices ↑J / I < I⁻¹ by
    obtain ⟨_, a, hI, hpI⟩ := SetLike.lt_iff_le_and_exists.mp this
    rw [mem_inv_iff hI0] at hI
    refine' ⟨a, fun i hi => _, _⟩
    -- By definition, `a ∈ I⁻¹` multiplies elements of `I` into elements of `1`,
    -- in other words, `a * f i` is an integer.
    · exact (mem_one_iff _).mp (hI (f i) (Submodule.subset_span (Set.mem_image_of_mem f hi)))
    · contrapose! hpI
      -- And if all `a`-multiples of `I` are an element of `J`,
      -- then `a` is actually an element of `J / I`, contradiction.
      refine' (mem_div_iff_of_nonzero hI0).mpr fun y hy => Submodule.span_induction hy _ _ _ _
      · rintro _ ⟨i, hi, rfl⟩; exact hpI i hi
      · rw [mul_zero]; exact Submodule.zero_mem _
      · intro x y hx hy; rw [mul_add]; exact Submodule.add_mem _ hx hy
      · intro b x hx; rw [mul_smul_comm]; exact Submodule.smul_mem _ b hx
  -- To show the inclusion of `J / I` into `I⁻¹ = 1 / I`, note that `J < I`.
  calc
    ↑J / I = ↑J * I⁻¹ := div_eq_mul_inv (↑J) I
    _ < 1 * I⁻¹ := (mul_right_strictMono (inv_ne_zero hI0) ?_)
    _ = I⁻¹ := one_mul _
  · 

Proof state:
R : Type u_1
A : Type u_2
K : Type u_3
inst✝⁶ : CommRing R
inst✝⁵ : CommRing A
inst✝⁴ : Field K
inst✝³ : IsDomain A
inst✝² : IsDedekindDomain A
inst✝¹ : Algebra A K
inst✝ : IsFractionRing A K
J : Ideal A
hJ : J ≠ ⊤
ι : Type u_4
s : Finset ι
f : ι → K
j : ι
hjs : j ∈ s
hjf : f j ≠ 0
I : FractionalIdeal A⁰ K := spanFinset A s f
hI0 : I ≠ 0
⊢ ↑J < 1

Next tactic:
rw [← coeIdeal_top]
/-- Strengthening of `IsLocalization.exist_integer_multiples`:
Let `J ≠ ⊤` be an ideal in a Dedekind domain `A`, and `f ≠ 0` a finite collection
of elements of `K = Frac(A)`, then we can multiply the elements of `f` by some `a : K`
to find a collection of elements of `A` that is not completely contained in `J`. -/
theorem Ideal.exist_integer_multiples_not_mem {J : Ideal A} (hJ : J ≠ ⊤) {ι : Type*} (s : Finset ι)
    (f : ι → K) {j} (hjs : j ∈ s) (hjf : f j ≠ 0) :
    ∃ a : K,
      (∀ i ∈ s, IsLocalization.IsInteger A (a * f i)) ∧
        ∃ i ∈ s, a * f i ∉ (J : FractionalIdeal A⁰ K) := by
  -- Consider the fractional ideal `I` spanned by the `f`s.
  let I : FractionalIdeal A⁰ K := spanFinset A s f
  have hI0 : I ≠ 0 := spanFinset_ne_zero.mpr ⟨j, hjs, hjf⟩
  -- We claim the multiplier `a` we're looking for is in `I⁻¹ \ (J / I)`.
  suffices ↑J / I < I⁻¹ by
    obtain ⟨_, a, hI, hpI⟩ := SetLike.lt_iff_le_and_exists.mp this
    rw [mem_inv_iff hI0] at hI
    refine' ⟨a, fun i hi => _, _⟩
    -- By definition, `a ∈ I⁻¹` multiplies elements of `I` into elements of `1`,
    -- in other words, `a * f i` is an integer.
    · exact (mem_one_iff _).mp (hI (f i) (Submodule.subset_span (Set.mem_image_of_mem f hi)))
    · contrapose! hpI
      -- And if all `a`-multiples of `I` are an element of `J`,
      -- then `a` is actually an element of `J / I`, contradiction.
      refine' (mem_div_iff_of_nonzero hI0).mpr fun y hy => Submodule.span_induction hy _ _ _ _
      · rintro _ ⟨i, hi, rfl⟩; exact hpI i hi
      · rw [mul_zero]; exact Submodule.zero_mem _
      · intro x y hx hy; rw [mul_add]; exact Submodule.add_mem _ hx hy
      · intro b x hx; rw [mul_smul_comm]; exact Submodule.smul_mem _ b hx
  -- To show the inclusion of `J / I` into `I⁻¹ = 1 / I`, note that `J < I`.
  calc
    ↑J / I = ↑J * I⁻¹ := div_eq_mul_inv (↑J) I
    _ < 1 * I⁻¹ := (mul_right_strictMono (inv_ne_zero hI0) ?_)
    _ = I⁻¹ := one_mul _
  · rw [← coeIdeal_top]
    -- And multiplying by `I⁻¹` is indeed strictly monotone.
    

Proof state:
R : Type u_1
A : Type u_2
K : Type u_3
inst✝⁶ : CommRing R
inst✝⁵ : CommRing A
inst✝⁴ : Field K
inst✝³ : IsDomain A
inst✝² : IsDedekindDomain A
inst✝¹ : Algebra A K
inst✝ : IsFractionRing A K
J : Ideal A
hJ : J ≠ ⊤
ι : Type u_4
s : Finset ι
f : ι → K
j : ι
hjs : j ∈ s
hjf : f j ≠ 0
I : FractionalIdeal A⁰ K := spanFinset A s f
hI0 : I ≠ 0
⊢ ↑J < ↑⊤

Next tactic:
exact
      strictMono_of_le_iff_le (fun _ _ => (coeIdeal_le_coeIdeal K).symm)
        (lt_top_iff_ne_top.mpr hJ)
@[simp]
theorem sup_mul_inf (I J : Ideal A) : (I ⊔ J) * (I ⊓ J) = I * J := by
  

Proof state:
R : Type u_1
A : Type u_2
K : Type u_3
inst✝⁶ : CommRing R
inst✝⁵ : CommRing A
inst✝⁴ : Field K
inst✝³ : IsDomain A
inst✝² : IsDedekindDomain A
inst✝¹ : Algebra A K
inst✝ : IsFractionRing A K
I J : Ideal A
⊢ (I ⊔ J) * (I ⊓ J) = I * J

Next tactic:
letI := Classical.decEq (Ideal A)
@[simp]
theorem sup_mul_inf (I J : Ideal A) : (I ⊔ J) * (I ⊓ J) = I * J := by
  letI := Classical.decEq (Ideal A)
  

Proof state:
R : Type u_1
A : Type u_2
K : Type u_3
inst✝⁶ : CommRing R
inst✝⁵ : CommRing A
inst✝⁴ : Field K
inst✝³ : IsDomain A
inst✝² : IsDedekindDomain A
inst✝¹ : Algebra A K
inst✝ : IsFractionRing A K
I J : Ideal A
this : DecidableEq (Ideal A) := Classical.decEq (Ideal A)
⊢ (I ⊔ J) * (I ⊓ J) = I * J

Next tactic:
letI := Classical.decEq (Associates (Ideal A))
@[simp]
theorem sup_mul_inf (I J : Ideal A) : (I ⊔ J) * (I ⊓ J) = I * J := by
  letI := Classical.decEq (Ideal A)
  letI := Classical.decEq (Associates (Ideal A))
  

Proof state:
R : Type u_1
A : Type u_2
K : Type u_3
inst✝⁶ : CommRing R
inst✝⁵ : CommRing A
inst✝⁴ : Field K
inst✝³ : IsDomain A
inst✝² : IsDedekindDomain A
inst✝¹ : Algebra A K
inst✝ : IsFractionRing A K
I J : Ideal A
this✝ : DecidableEq (Ideal A) := Classical.decEq (Ideal A)
this : DecidableEq (Associates (Ideal A)) := Classical.decEq (Associates (Ideal A))
⊢ (I ⊔ J) * (I ⊓ J) = I * J

Next tactic:
letI := UniqueFactorizationMonoid.toNormalizedGCDMonoid (Ideal A)
@[simp]
theorem sup_mul_inf (I J : Ideal A) : (I ⊔ J) * (I ⊓ J) = I * J := by
  letI := Classical.decEq (Ideal A)
  letI := Classical.decEq (Associates (Ideal A))
  letI := UniqueFactorizationMonoid.toNormalizedGCDMonoid (Ideal A)
  

Proof state:
R : Type u_1
A : Type u_2
K : Type u_3
inst✝⁶ : CommRing R
inst✝⁵ : CommRing A
inst✝⁴ : Field K
inst✝³ : IsDomain A
inst✝² : IsDedekindDomain A
inst✝¹ : Algebra A K
inst✝ : IsFractionRing A K
I J : Ideal A
this✝¹ : DecidableEq (Ideal A) := Classical.decEq (Ideal A)
this✝ : DecidableEq (Associates (Ideal A)) := Classical.decEq (Associates (Ideal A))
this : NormalizedGCDMonoid (Ideal A) := toNormalizedGCDMonoid (Ideal A)
⊢ (I ⊔ J) * (I ⊓ J) = I * J

Next tactic:
have hgcd : gcd I J = I ⊔ J := by
    rw [gcd_eq_normalize _ _, normalize_eq]
    · rw [dvd_iff_le, sup_le_iff, ← dvd_iff_le, ← dvd_iff_le]
      exact ⟨gcd_dvd_left _ _, gcd_dvd_right _ _⟩
    · rw [dvd_gcd_iff, dvd_iff_le, dvd_iff_le]
      simp
@[simp]
theorem sup_mul_inf (I J : Ideal A) : (I ⊔ J) * (I ⊓ J) = I * J := by
  letI := Classical.decEq (Ideal A)
  letI := Classical.decEq (Associates (Ideal A))
  letI := UniqueFactorizationMonoid.toNormalizedGCDMonoid (Ideal A)
  have hgcd : gcd I J = I ⊔ J := by
    

Proof state:
R : Type u_1
A : Type u_2
K : Type u_3
inst✝⁶ : CommRing R
inst✝⁵ : CommRing A
inst✝⁴ : Field K
inst✝³ : IsDomain A
inst✝² : IsDedekindDomain A
inst✝¹ : Algebra A K
inst✝ : IsFractionRing A K
I J : Ideal A
this✝¹ : DecidableEq (Ideal A) := Classical.decEq (Ideal A)
this✝ : DecidableEq (Associates (Ideal A)) := Classical.decEq (Associates (Ideal A))
this : NormalizedGCDMonoid (Ideal A) := toNormalizedGCDMonoid (Ideal A)
⊢ gcd I J = I ⊔ J

Next tactic:
rw [gcd_eq_normalize _ _, normalize_eq]
@[simp]
theorem sup_mul_inf (I J : Ideal A) : (I ⊔ J) * (I ⊓ J) = I * J := by
  letI := Classical.decEq (Ideal A)
  letI := Classical.decEq (Associates (Ideal A))
  letI := UniqueFactorizationMonoid.toNormalizedGCDMonoid (Ideal A)
  have hgcd : gcd I J = I ⊔ J := by
    rw [gcd_eq_normalize _ _, normalize_eq]
    · 

Proof state:
R : Type u_1
A : Type u_2
K : Type u_3
inst✝⁶ : CommRing R
inst✝⁵ : CommRing A
inst✝⁴ : Field K
inst✝³ : IsDomain A
inst✝² : IsDedekindDomain A
inst✝¹ : Algebra A K
inst✝ : IsFractionRing A K
I J : Ideal A
this✝¹ : DecidableEq (Ideal A) := Classical.decEq (Ideal A)
this✝ : DecidableEq (Associates (Ideal A)) := Classical.decEq (Associates (Ideal A))
this : NormalizedGCDMonoid (Ideal A) := toNormalizedGCDMonoid (Ideal A)
⊢ gcd I J ∣ I ⊔ J

Next tactic:
rw [dvd_iff_le, sup_le_iff, ← dvd_iff_le, ← dvd_iff_le]
@[simp]
theorem sup_mul_inf (I J : Ideal A) : (I ⊔ J) * (I ⊓ J) = I * J := by
  letI := Classical.decEq (Ideal A)
  letI := Classical.decEq (Associates (Ideal A))
  letI := UniqueFactorizationMonoid.toNormalizedGCDMonoid (Ideal A)
  have hgcd : gcd I J = I ⊔ J := by
    rw [gcd_eq_normalize _ _, normalize_eq]
    · rw [dvd_iff_le, sup_le_iff, ← dvd_iff_le, ← dvd_iff_le]
      

Proof state:
R : Type u_1
A : Type u_2
K : Type u_3
inst✝⁶ : CommRing R
inst✝⁵ : CommRing A
inst✝⁴ : Field K
inst✝³ : IsDomain A
inst✝² : IsDedekindDomain A
inst✝¹ : Algebra A K
inst✝ : IsFractionRing A K
I J : Ideal A
this✝¹ : DecidableEq (Ideal A) := Classical.decEq (Ideal A)
this✝ : DecidableEq (Associates (Ideal A)) := Classical.decEq (Associates (Ideal A))
this : NormalizedGCDMonoid (Ideal A) := toNormalizedGCDMonoid (Ideal A)
⊢ gcd I J ∣ I ∧ gcd I J ∣ J

Next tactic:
exact ⟨gcd_dvd_left _ _, gcd_dvd_right _ _⟩
@[simp]
theorem sup_mul_inf (I J : Ideal A) : (I ⊔ J) * (I ⊓ J) = I * J := by
  letI := Classical.decEq (Ideal A)
  letI := Classical.decEq (Associates (Ideal A))
  letI := UniqueFactorizationMonoid.toNormalizedGCDMonoid (Ideal A)
  have hgcd : gcd I J = I ⊔ J := by
    rw [gcd_eq_normalize _ _, normalize_eq]
    · rw [dvd_iff_le, sup_le_iff, ← dvd_iff_le, ← dvd_iff_le]
      exact ⟨gcd_dvd_left _ _, gcd_dvd_right _ _⟩
    · 

Proof state:
R : Type u_1
A : Type u_2
K : Type u_3
inst✝⁶ : CommRing R
inst✝⁵ : CommRing A
inst✝⁴ : Field K
inst✝³ : IsDomain A
inst✝² : IsDedekindDomain A
inst✝¹ : Algebra A K
inst✝ : IsFractionRing A K
I J : Ideal A
this✝¹ : DecidableEq (Ideal A) := Classical.decEq (Ideal A)
this✝ : DecidableEq (Associates (Ideal A)) := Classical.decEq (Associates (Ideal A))
this : NormalizedGCDMonoid (Ideal A) := toNormalizedGCDMonoid (Ideal A)
⊢ I ⊔ J ∣ gcd I J

Next tactic:
rw [dvd_gcd_iff, dvd_iff_le, dvd_iff_le]
@[simp]
theorem sup_mul_inf (I J : Ideal A) : (I ⊔ J) * (I ⊓ J) = I * J := by
  letI := Classical.decEq (Ideal A)
  letI := Classical.decEq (Associates (Ideal A))
  letI := UniqueFactorizationMonoid.toNormalizedGCDMonoid (Ideal A)
  have hgcd : gcd I J = I ⊔ J := by
    rw [gcd_eq_normalize _ _, normalize_eq]
    · rw [dvd_iff_le, sup_le_iff, ← dvd_iff_le, ← dvd_iff_le]
      exact ⟨gcd_dvd_left _ _, gcd_dvd_right _ _⟩
    · rw [dvd_gcd_iff, dvd_iff_le, dvd_iff_le]
      

Proof state:
R : Type u_1
A : Type u_2
K : Type u_3
inst✝⁶ : CommRing R
inst✝⁵ : CommRing A
inst✝⁴ : Field K
inst✝³ : IsDomain A
inst✝² : IsDedekindDomain A
inst✝¹ : Algebra A K
inst✝ : IsFractionRing A K
I J : Ideal A
this✝¹ : DecidableEq (Ideal A) := Classical.decEq (Ideal A)
this✝ : DecidableEq (Associates (Ideal A)) := Classical.decEq (Associates (Ideal A))
this : NormalizedGCDMonoid (Ideal A) := toNormalizedGCDMonoid (Ideal A)
⊢ I ≤ I ⊔ J ∧ J ≤ I ⊔ J

Next tactic:
simp
@[simp]
theorem sup_mul_inf (I J : Ideal A) : (I ⊔ J) * (I ⊓ J) = I * J := by
  letI := Classical.decEq (Ideal A)
  letI := Classical.decEq (Associates (Ideal A))
  letI := UniqueFactorizationMonoid.toNormalizedGCDMonoid (Ideal A)
  have hgcd : gcd I J = I ⊔ J := by
    rw [gcd_eq_normalize _ _, normalize_eq]
    · rw [dvd_iff_le, sup_le_iff, ← dvd_iff_le, ← dvd_iff_le]
      exact ⟨gcd_dvd_left _ _, gcd_dvd_right _ _⟩
    · rw [dvd_gcd_iff, dvd_iff_le, dvd_iff_le]
      simp
  

Proof state:
R : Type u_1
A : Type u_2
K : Type u_3
inst✝⁶ : CommRing R
inst✝⁵ : CommRing A
inst✝⁴ : Field K
inst✝³ : IsDomain A
inst✝² : IsDedekindDomain A
inst✝¹ : Algebra A K
inst✝ : IsFractionRing A K
I J : Ideal A
this✝¹ : DecidableEq (Ideal A) := Classical.decEq (Ideal A)
this✝ : DecidableEq (Associates (Ideal A)) := Classical.decEq (Associates (Ideal A))
this : NormalizedGCDMonoid (Ideal A) := toNormalizedGCDMonoid (Ideal A)
hgcd : gcd I J = I ⊔ J
⊢ (I ⊔ J) * (I ⊓ J) = I * J

Next tactic:
have hlcm : lcm I J = I ⊓ J := by
    rw [lcm_eq_normalize _ _, normalize_eq]
    · rw [lcm_dvd_iff, dvd_iff_le, dvd_iff_le]
      simp
    · rw [dvd_iff_le, le_inf_iff, ← dvd_iff_le, ← dvd_iff_le]
      exact ⟨dvd_lcm_left _ _, dvd_lcm_right _ _⟩
@[simp]
theorem sup_mul_inf (I J : Ideal A) : (I ⊔ J) * (I ⊓ J) = I * J := by
  letI := Classical.decEq (Ideal A)
  letI := Classical.decEq (Associates (Ideal A))
  letI := UniqueFactorizationMonoid.toNormalizedGCDMonoid (Ideal A)
  have hgcd : gcd I J = I ⊔ J := by
    rw [gcd_eq_normalize _ _, normalize_eq]
    · rw [dvd_iff_le, sup_le_iff, ← dvd_iff_le, ← dvd_iff_le]
      exact ⟨gcd_dvd_left _ _, gcd_dvd_right _ _⟩
    · rw [dvd_gcd_iff, dvd_iff_le, dvd_iff_le]
      simp
  have hlcm : lcm I J = I ⊓ J := by
    

Proof state:
R : Type u_1
A : Type u_2
K : Type u_3
inst✝⁶ : CommRing R
inst✝⁵ : CommRing A
inst✝⁴ : Field K
inst✝³ : IsDomain A
inst✝² : IsDedekindDomain A
inst✝¹ : Algebra A K
inst✝ : IsFractionRing A K
I J : Ideal A
this✝¹ : DecidableEq (Ideal A) := Classical.decEq (Ideal A)
this✝ : DecidableEq (Associates (Ideal A)) := Classical.decEq (Associates (Ideal A))
this : NormalizedGCDMonoid (Ideal A) := toNormalizedGCDMonoid (Ideal A)
hgcd : gcd I J = I ⊔ J
⊢ lcm I J = I ⊓ J

Next tactic:
rw [lcm_eq_normalize _ _, normalize_eq]
@[simp]
theorem sup_mul_inf (I J : Ideal A) : (I ⊔ J) * (I ⊓ J) = I * J := by
  letI := Classical.decEq (Ideal A)
  letI := Classical.decEq (Associates (Ideal A))
  letI := UniqueFactorizationMonoid.toNormalizedGCDMonoid (Ideal A)
  have hgcd : gcd I J = I ⊔ J := by
    rw [gcd_eq_normalize _ _, normalize_eq]
    · rw [dvd_iff_le, sup_le_iff, ← dvd_iff_le, ← dvd_iff_le]
      exact ⟨gcd_dvd_left _ _, gcd_dvd_right _ _⟩
    · rw [dvd_gcd_iff, dvd_iff_le, dvd_iff_le]
      simp
  have hlcm : lcm I J = I ⊓ J := by
    rw [lcm_eq_normalize _ _, normalize_eq]
    · 

Proof state:
R : Type u_1
A : Type u_2
K : Type u_3
inst✝⁶ : CommRing R
inst✝⁵ : CommRing A
inst✝⁴ : Field K
inst✝³ : IsDomain A
inst✝² : IsDedekindDomain A
inst✝¹ : Algebra A K
inst✝ : IsFractionRing A K
I J : Ideal A
this✝¹ : DecidableEq (Ideal A) := Classical.decEq (Ideal A)
this✝ : DecidableEq (Associates (Ideal A)) := Classical.decEq (Associates (Ideal A))
this : NormalizedGCDMonoid (Ideal A) := toNormalizedGCDMonoid (Ideal A)
hgcd : gcd I J = I ⊔ J
⊢ lcm I J ∣ I ⊓ J

Next tactic:
rw [lcm_dvd_iff, dvd_iff_le, dvd_iff_le]