l3lab/ntp-mathlib huggingface dataset:
theorem of_ufd_of_unique_irreducible [UniqueFactorizationMonoid R] (h₁ : ∃ p : R, Irreducible p)
    (h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q) :
    HasUnitMulPowIrreducibleFactorization R := by
  

Proof state:
R : Type u_1
inst✝² : CommRing R
hR : HasUnitMulPowIrreducibleFactorization R
inst✝¹ : IsDomain R
inst✝ : UniqueFactorizationMonoid R
h₁ : ∃ p, Irreducible p
h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q
⊢ HasUnitMulPowIrreducibleFactorization R

Next tactic:
obtain ⟨p, hp⟩ := h₁
theorem of_ufd_of_unique_irreducible [UniqueFactorizationMonoid R] (h₁ : ∃ p : R, Irreducible p)
    (h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q) :
    HasUnitMulPowIrreducibleFactorization R := by
  obtain ⟨p, hp⟩ := h₁
  

Proof state:
case intro
R : Type u_1
inst✝² : CommRing R
hR : HasUnitMulPowIrreducibleFactorization R
inst✝¹ : IsDomain R
inst✝ : UniqueFactorizationMonoid R
h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q
p : R
hp : Irreducible p
⊢ HasUnitMulPowIrreducibleFactorization R

Next tactic:
refine' ⟨p, hp, _⟩
theorem of_ufd_of_unique_irreducible [UniqueFactorizationMonoid R] (h₁ : ∃ p : R, Irreducible p)
    (h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q) :
    HasUnitMulPowIrreducibleFactorization R := by
  obtain ⟨p, hp⟩ := h₁
  refine' ⟨p, hp, _⟩
  

Proof state:
case intro
R : Type u_1
inst✝² : CommRing R
hR : HasUnitMulPowIrreducibleFactorization R
inst✝¹ : IsDomain R
inst✝ : UniqueFactorizationMonoid R
h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q
p : R
hp : Irreducible p
⊢ ∀ {x : R}, x ≠ 0 → ∃ n, Associated (p ^ n) x

Next tactic:
intro x hx
theorem of_ufd_of_unique_irreducible [UniqueFactorizationMonoid R] (h₁ : ∃ p : R, Irreducible p)
    (h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q) :
    HasUnitMulPowIrreducibleFactorization R := by
  obtain ⟨p, hp⟩ := h₁
  refine' ⟨p, hp, _⟩
  intro x hx
  

Proof state:
case intro
R : Type u_1
inst✝² : CommRing R
hR : HasUnitMulPowIrreducibleFactorization R
inst✝¹ : IsDomain R
inst✝ : UniqueFactorizationMonoid R
h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q
p : R
hp : Irreducible p
x : R
hx : x ≠ 0
⊢ ∃ n, Associated (p ^ n) x

Next tactic:
cases' WfDvdMonoid.exists_factors x hx with fx hfx
theorem of_ufd_of_unique_irreducible [UniqueFactorizationMonoid R] (h₁ : ∃ p : R, Irreducible p)
    (h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q) :
    HasUnitMulPowIrreducibleFactorization R := by
  obtain ⟨p, hp⟩ := h₁
  refine' ⟨p, hp, _⟩
  intro x hx
  cases' WfDvdMonoid.exists_factors x hx with fx hfx
  

Proof state:
case intro.intro
R : Type u_1
inst✝² : CommRing R
hR : HasUnitMulPowIrreducibleFactorization R
inst✝¹ : IsDomain R
inst✝ : UniqueFactorizationMonoid R
h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q
p : R
hp : Irreducible p
x : R
hx : x ≠ 0
fx : Multiset R
hfx : (∀ b ∈ fx, Irreducible b) ∧ Associated (Multiset.prod fx) x
⊢ ∃ n, Associated (p ^ n) x

Next tactic:
refine' ⟨Multiset.card fx, _⟩
theorem of_ufd_of_unique_irreducible [UniqueFactorizationMonoid R] (h₁ : ∃ p : R, Irreducible p)
    (h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q) :
    HasUnitMulPowIrreducibleFactorization R := by
  obtain ⟨p, hp⟩ := h₁
  refine' ⟨p, hp, _⟩
  intro x hx
  cases' WfDvdMonoid.exists_factors x hx with fx hfx
  refine' ⟨Multiset.card fx, _⟩
  

Proof state:
case intro.intro
R : Type u_1
inst✝² : CommRing R
hR : HasUnitMulPowIrreducibleFactorization R
inst✝¹ : IsDomain R
inst✝ : UniqueFactorizationMonoid R
h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q
p : R
hp : Irreducible p
x : R
hx : x ≠ 0
fx : Multiset R
hfx : (∀ b ∈ fx, Irreducible b) ∧ Associated (Multiset.prod fx) x
⊢ Associated (p ^ Multiset.card fx) x

Next tactic:
have H := hfx.2
theorem of_ufd_of_unique_irreducible [UniqueFactorizationMonoid R] (h₁ : ∃ p : R, Irreducible p)
    (h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q) :
    HasUnitMulPowIrreducibleFactorization R := by
  obtain ⟨p, hp⟩ := h₁
  refine' ⟨p, hp, _⟩
  intro x hx
  cases' WfDvdMonoid.exists_factors x hx with fx hfx
  refine' ⟨Multiset.card fx, _⟩
  have H := hfx.2
  

Proof state:
case intro.intro
R : Type u_1
inst✝² : CommRing R
hR : HasUnitMulPowIrreducibleFactorization R
inst✝¹ : IsDomain R
inst✝ : UniqueFactorizationMonoid R
h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q
p : R
hp : Irreducible p
x : R
hx : x ≠ 0
fx : Multiset R
hfx : (∀ b ∈ fx, Irreducible b) ∧ Associated (Multiset.prod fx) x
H : Associated (Multiset.prod fx) x
⊢ Associated (p ^ Multiset.card fx) x

Next tactic:
rw [← Associates.mk_eq_mk_iff_associated] at H ⊢
theorem of_ufd_of_unique_irreducible [UniqueFactorizationMonoid R] (h₁ : ∃ p : R, Irreducible p)
    (h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q) :
    HasUnitMulPowIrreducibleFactorization R := by
  obtain ⟨p, hp⟩ := h₁
  refine' ⟨p, hp, _⟩
  intro x hx
  cases' WfDvdMonoid.exists_factors x hx with fx hfx
  refine' ⟨Multiset.card fx, _⟩
  have H := hfx.2
  rw [← Associates.mk_eq_mk_iff_associated] at H ⊢
  

Proof state:
case intro.intro
R : Type u_1
inst✝² : CommRing R
hR : HasUnitMulPowIrreducibleFactorization R
inst✝¹ : IsDomain R
inst✝ : UniqueFactorizationMonoid R
h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q
p : R
hp : Irreducible p
x : R
hx : x ≠ 0
fx : Multiset R
hfx : (∀ b ∈ fx, Irreducible b) ∧ Associated (Multiset.prod fx) x
H : Associates.mk (Multiset.prod fx) = Associates.mk x
⊢ Associates.mk (p ^ Multiset.card fx) = Associates.mk x

Next tactic:
rw [← H, ← Associates.prod_mk, Associates.mk_pow, ← Multiset.prod_replicate]
theorem of_ufd_of_unique_irreducible [UniqueFactorizationMonoid R] (h₁ : ∃ p : R, Irreducible p)
    (h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q) :
    HasUnitMulPowIrreducibleFactorization R := by
  obtain ⟨p, hp⟩ := h₁
  refine' ⟨p, hp, _⟩
  intro x hx
  cases' WfDvdMonoid.exists_factors x hx with fx hfx
  refine' ⟨Multiset.card fx, _⟩
  have H := hfx.2
  rw [← Associates.mk_eq_mk_iff_associated] at H ⊢
  rw [← H, ← Associates.prod_mk, Associates.mk_pow, ← Multiset.prod_replicate]
  

Proof state:
case intro.intro
R : Type u_1
inst✝² : CommRing R
hR : HasUnitMulPowIrreducibleFactorization R
inst✝¹ : IsDomain R
inst✝ : UniqueFactorizationMonoid R
h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q
p : R
hp : Irreducible p
x : R
hx : x ≠ 0
fx : Multiset R
hfx : (∀ b ∈ fx, Irreducible b) ∧ Associated (Multiset.prod fx) x
H : Associates.mk (Multiset.prod fx) = Associates.mk x
⊢ Multiset.prod (Multiset.replicate (Multiset.card fx) (Associates.mk p)) =
    Multiset.prod (Multiset.map Associates.mk fx)

Next tactic:
congr 1
theorem of_ufd_of_unique_irreducible [UniqueFactorizationMonoid R] (h₁ : ∃ p : R, Irreducible p)
    (h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q) :
    HasUnitMulPowIrreducibleFactorization R := by
  obtain ⟨p, hp⟩ := h₁
  refine' ⟨p, hp, _⟩
  intro x hx
  cases' WfDvdMonoid.exists_factors x hx with fx hfx
  refine' ⟨Multiset.card fx, _⟩
  have H := hfx.2
  rw [← Associates.mk_eq_mk_iff_associated] at H ⊢
  rw [← H, ← Associates.prod_mk, Associates.mk_pow, ← Multiset.prod_replicate]
  congr 1
  

Proof state:
case intro.intro.e_a
R : Type u_1
inst✝² : CommRing R
hR : HasUnitMulPowIrreducibleFactorization R
inst✝¹ : IsDomain R
inst✝ : UniqueFactorizationMonoid R
h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q
p : R
hp : Irreducible p
x : R
hx : x ≠ 0
fx : Multiset R
hfx : (∀ b ∈ fx, Irreducible b) ∧ Associated (Multiset.prod fx) x
H : Associates.mk (Multiset.prod fx) = Associates.mk x
⊢ Multiset.replicate (Multiset.card fx) (Associates.mk p) = Multiset.map Associates.mk fx

Next tactic:
symm
theorem of_ufd_of_unique_irreducible [UniqueFactorizationMonoid R] (h₁ : ∃ p : R, Irreducible p)
    (h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q) :
    HasUnitMulPowIrreducibleFactorization R := by
  obtain ⟨p, hp⟩ := h₁
  refine' ⟨p, hp, _⟩
  intro x hx
  cases' WfDvdMonoid.exists_factors x hx with fx hfx
  refine' ⟨Multiset.card fx, _⟩
  have H := hfx.2
  rw [← Associates.mk_eq_mk_iff_associated] at H ⊢
  rw [← H, ← Associates.prod_mk, Associates.mk_pow, ← Multiset.prod_replicate]
  congr 1
  symm
  

Proof state:
case intro.intro.e_a
R : Type u_1
inst✝² : CommRing R
hR : HasUnitMulPowIrreducibleFactorization R
inst✝¹ : IsDomain R
inst✝ : UniqueFactorizationMonoid R
h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q
p : R
hp : Irreducible p
x : R
hx : x ≠ 0
fx : Multiset R
hfx : (∀ b ∈ fx, Irreducible b) ∧ Associated (Multiset.prod fx) x
H : Associates.mk (Multiset.prod fx) = Associates.mk x
⊢ Multiset.map Associates.mk fx = Multiset.replicate (Multiset.card fx) (Associates.mk p)

Next tactic:
rw [Multiset.eq_replicate]
theorem of_ufd_of_unique_irreducible [UniqueFactorizationMonoid R] (h₁ : ∃ p : R, Irreducible p)
    (h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q) :
    HasUnitMulPowIrreducibleFactorization R := by
  obtain ⟨p, hp⟩ := h₁
  refine' ⟨p, hp, _⟩
  intro x hx
  cases' WfDvdMonoid.exists_factors x hx with fx hfx
  refine' ⟨Multiset.card fx, _⟩
  have H := hfx.2
  rw [← Associates.mk_eq_mk_iff_associated] at H ⊢
  rw [← H, ← Associates.prod_mk, Associates.mk_pow, ← Multiset.prod_replicate]
  congr 1
  symm
  rw [Multiset.eq_replicate]
  

Proof state:
case intro.intro.e_a
R : Type u_1
inst✝² : CommRing R
hR : HasUnitMulPowIrreducibleFactorization R
inst✝¹ : IsDomain R
inst✝ : UniqueFactorizationMonoid R
h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q
p : R
hp : Irreducible p
x : R
hx : x ≠ 0
fx : Multiset R
hfx : (∀ b ∈ fx, Irreducible b) ∧ Associated (Multiset.prod fx) x
H : Associates.mk (Multiset.prod fx) = Associates.mk x
⊢ Multiset.card (Multiset.map Associates.mk fx) = Multiset.card fx ∧
    ∀ b ∈ Multiset.map Associates.mk fx, b = Associates.mk p

Next tactic:
simp only [true_and_iff, and_imp, Multiset.card_map, eq_self_iff_true, Multiset.mem_map,
    exists_imp]
theorem of_ufd_of_unique_irreducible [UniqueFactorizationMonoid R] (h₁ : ∃ p : R, Irreducible p)
    (h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q) :
    HasUnitMulPowIrreducibleFactorization R := by
  obtain ⟨p, hp⟩ := h₁
  refine' ⟨p, hp, _⟩
  intro x hx
  cases' WfDvdMonoid.exists_factors x hx with fx hfx
  refine' ⟨Multiset.card fx, _⟩
  have H := hfx.2
  rw [← Associates.mk_eq_mk_iff_associated] at H ⊢
  rw [← H, ← Associates.prod_mk, Associates.mk_pow, ← Multiset.prod_replicate]
  congr 1
  symm
  rw [Multiset.eq_replicate]
  simp only [true_and_iff, and_imp, Multiset.card_map, eq_self_iff_true, Multiset.mem_map,
    exists_imp]
  

Proof state:
case intro.intro.e_a
R : Type u_1
inst✝² : CommRing R
hR : HasUnitMulPowIrreducibleFactorization R
inst✝¹ : IsDomain R
inst✝ : UniqueFactorizationMonoid R
h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q
p : R
hp : Irreducible p
x : R
hx : x ≠ 0
fx : Multiset R
hfx : (∀ b ∈ fx, Irreducible b) ∧ Associated (Multiset.prod fx) x
H : Associates.mk (Multiset.prod fx) = Associates.mk x
⊢ ∀ (b : Associates R), ∀ x ∈ fx, Associates.mk x = b → b = Associates.mk p

Next tactic:
rintro _ q hq rfl
theorem of_ufd_of_unique_irreducible [UniqueFactorizationMonoid R] (h₁ : ∃ p : R, Irreducible p)
    (h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q) :
    HasUnitMulPowIrreducibleFactorization R := by
  obtain ⟨p, hp⟩ := h₁
  refine' ⟨p, hp, _⟩
  intro x hx
  cases' WfDvdMonoid.exists_factors x hx with fx hfx
  refine' ⟨Multiset.card fx, _⟩
  have H := hfx.2
  rw [← Associates.mk_eq_mk_iff_associated] at H ⊢
  rw [← H, ← Associates.prod_mk, Associates.mk_pow, ← Multiset.prod_replicate]
  congr 1
  symm
  rw [Multiset.eq_replicate]
  simp only [true_and_iff, and_imp, Multiset.card_map, eq_self_iff_true, Multiset.mem_map,
    exists_imp]
  rintro _ q hq rfl
  

Proof state:
case intro.intro.e_a
R : Type u_1
inst✝² : CommRing R
hR : HasUnitMulPowIrreducibleFactorization R
inst✝¹ : IsDomain R
inst✝ : UniqueFactorizationMonoid R
h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q
p : R
hp : Irreducible p
x : R
hx : x ≠ 0
fx : Multiset R
hfx : (∀ b ∈ fx, Irreducible b) ∧ Associated (Multiset.prod fx) x
H : Associates.mk (Multiset.prod fx) = Associates.mk x
q : R
hq : q ∈ fx
⊢ Associates.mk q = Associates.mk p

Next tactic:
rw [Associates.mk_eq_mk_iff_associated]
theorem of_ufd_of_unique_irreducible [UniqueFactorizationMonoid R] (h₁ : ∃ p : R, Irreducible p)
    (h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q) :
    HasUnitMulPowIrreducibleFactorization R := by
  obtain ⟨p, hp⟩ := h₁
  refine' ⟨p, hp, _⟩
  intro x hx
  cases' WfDvdMonoid.exists_factors x hx with fx hfx
  refine' ⟨Multiset.card fx, _⟩
  have H := hfx.2
  rw [← Associates.mk_eq_mk_iff_associated] at H ⊢
  rw [← H, ← Associates.prod_mk, Associates.mk_pow, ← Multiset.prod_replicate]
  congr 1
  symm
  rw [Multiset.eq_replicate]
  simp only [true_and_iff, and_imp, Multiset.card_map, eq_self_iff_true, Multiset.mem_map,
    exists_imp]
  rintro _ q hq rfl
  rw [Associates.mk_eq_mk_iff_associated]
  

Proof state:
case intro.intro.e_a
R : Type u_1
inst✝² : CommRing R
hR : HasUnitMulPowIrreducibleFactorization R
inst✝¹ : IsDomain R
inst✝ : UniqueFactorizationMonoid R
h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q
p : R
hp : Irreducible p
x : R
hx : x ≠ 0
fx : Multiset R
hfx : (∀ b ∈ fx, Irreducible b) ∧ Associated (Multiset.prod fx) x
H : Associates.mk (Multiset.prod fx) = Associates.mk x
q : R
hq : q ∈ fx
⊢ Associated q p

Next tactic:
apply h₂ (hfx.1 _ hq) hp
theorem aux_pid_of_ufd_of_unique_irreducible (R : Type u) [CommRing R] [IsDomain R]
    [UniqueFactorizationMonoid R] (h₁ : ∃ p : R, Irreducible p)
    (h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q) :
    IsPrincipalIdealRing R := by
  

Proof state:
R✝ : Type u_1
R : Type u
inst✝² : CommRing R
inst✝¹ : IsDomain R
inst✝ : UniqueFactorizationMonoid R
h₁ : ∃ p, Irreducible p
h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q
⊢ IsPrincipalIdealRing R

Next tactic:
constructor
theorem aux_pid_of_ufd_of_unique_irreducible (R : Type u) [CommRing R] [IsDomain R]
    [UniqueFactorizationMonoid R] (h₁ : ∃ p : R, Irreducible p)
    (h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q) :
    IsPrincipalIdealRing R := by
  constructor
  

Proof state:
case principal
R✝ : Type u_1
R : Type u
inst✝² : CommRing R
inst✝¹ : IsDomain R
inst✝ : UniqueFactorizationMonoid R
h₁ : ∃ p, Irreducible p
h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q
⊢ ∀ (S : Ideal R), Submodule.IsPrincipal S

Next tactic:
intro I
theorem aux_pid_of_ufd_of_unique_irreducible (R : Type u) [CommRing R] [IsDomain R]
    [UniqueFactorizationMonoid R] (h₁ : ∃ p : R, Irreducible p)
    (h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q) :
    IsPrincipalIdealRing R := by
  constructor
  intro I
  

Proof state:
case principal
R✝ : Type u_1
R : Type u
inst✝² : CommRing R
inst✝¹ : IsDomain R
inst✝ : UniqueFactorizationMonoid R
h₁ : ∃ p, Irreducible p
h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q
I : Ideal R
⊢ Submodule.IsPrincipal I

Next tactic:
by_cases I0 : I = ⊥
theorem aux_pid_of_ufd_of_unique_irreducible (R : Type u) [CommRing R] [IsDomain R]
    [UniqueFactorizationMonoid R] (h₁ : ∃ p : R, Irreducible p)
    (h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q) :
    IsPrincipalIdealRing R := by
  constructor
  intro I
  by_cases I0 : I = ⊥
  · 

Proof state:
case pos
R✝ : Type u_1
R : Type u
inst✝² : CommRing R
inst✝¹ : IsDomain R
inst✝ : UniqueFactorizationMonoid R
h₁ : ∃ p, Irreducible p
h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q
I : Ideal R
I0 : I = ⊥
⊢ Submodule.IsPrincipal I

Next tactic:
rw [I0]
theorem aux_pid_of_ufd_of_unique_irreducible (R : Type u) [CommRing R] [IsDomain R]
    [UniqueFactorizationMonoid R] (h₁ : ∃ p : R, Irreducible p)
    (h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q) :
    IsPrincipalIdealRing R := by
  constructor
  intro I
  by_cases I0 : I = ⊥
  · rw [I0]
    

Proof state:
case pos
R✝ : Type u_1
R : Type u
inst✝² : CommRing R
inst✝¹ : IsDomain R
inst✝ : UniqueFactorizationMonoid R
h₁ : ∃ p, Irreducible p
h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q
I : Ideal R
I0 : I = ⊥
⊢ Submodule.IsPrincipal ⊥

Next tactic:
use 0
theorem aux_pid_of_ufd_of_unique_irreducible (R : Type u) [CommRing R] [IsDomain R]
    [UniqueFactorizationMonoid R] (h₁ : ∃ p : R, Irreducible p)
    (h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q) :
    IsPrincipalIdealRing R := by
  constructor
  intro I
  by_cases I0 : I = ⊥
  · rw [I0]
    use 0
    

Proof state:
case h
R✝ : Type u_1
R : Type u
inst✝² : CommRing R
inst✝¹ : IsDomain R
inst✝ : UniqueFactorizationMonoid R
h₁ : ∃ p, Irreducible p
h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q
I : Ideal R
I0 : I = ⊥
⊢ ⊥ = Submodule.span R {0}

Next tactic:
simp only [Set.singleton_zero, Submodule.span_zero]
theorem aux_pid_of_ufd_of_unique_irreducible (R : Type u) [CommRing R] [IsDomain R]
    [UniqueFactorizationMonoid R] (h₁ : ∃ p : R, Irreducible p)
    (h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q) :
    IsPrincipalIdealRing R := by
  constructor
  intro I
  by_cases I0 : I = ⊥
  · rw [I0]
    use 0
    simp only [Set.singleton_zero, Submodule.span_zero]
  

Proof state:
case neg
R✝ : Type u_1
R : Type u
inst✝² : CommRing R
inst✝¹ : IsDomain R
inst✝ : UniqueFactorizationMonoid R
h₁ : ∃ p, Irreducible p
h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q
I : Ideal R
I0 : ¬I = ⊥
⊢ Submodule.IsPrincipal I

Next tactic:
obtain ⟨x, hxI, hx0⟩ : ∃ x ∈ I, x ≠ (0 : R) := I.ne_bot_iff.mp I0
theorem aux_pid_of_ufd_of_unique_irreducible (R : Type u) [CommRing R] [IsDomain R]
    [UniqueFactorizationMonoid R] (h₁ : ∃ p : R, Irreducible p)
    (h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q) :
    IsPrincipalIdealRing R := by
  constructor
  intro I
  by_cases I0 : I = ⊥
  · rw [I0]
    use 0
    simp only [Set.singleton_zero, Submodule.span_zero]
  obtain ⟨x, hxI, hx0⟩ : ∃ x ∈ I, x ≠ (0 : R) := I.ne_bot_iff.mp I0
  

Proof state:
case neg.intro.intro
R✝ : Type u_1
R : Type u
inst✝² : CommRing R
inst✝¹ : IsDomain R
inst✝ : UniqueFactorizationMonoid R
h₁ : ∃ p, Irreducible p
h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q
I : Ideal R
I0 : ¬I = ⊥
x : R
hxI : x ∈ I
hx0 : x ≠ 0
⊢ Submodule.IsPrincipal I

Next tactic:
obtain ⟨p, _, H⟩ := HasUnitMulPowIrreducibleFactorization.of_ufd_of_unique_irreducible h₁ h₂
theorem aux_pid_of_ufd_of_unique_irreducible (R : Type u) [CommRing R] [IsDomain R]
    [UniqueFactorizationMonoid R] (h₁ : ∃ p : R, Irreducible p)
    (h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q) :
    IsPrincipalIdealRing R := by
  constructor
  intro I
  by_cases I0 : I = ⊥
  · rw [I0]
    use 0
    simp only [Set.singleton_zero, Submodule.span_zero]
  obtain ⟨x, hxI, hx0⟩ : ∃ x ∈ I, x ≠ (0 : R) := I.ne_bot_iff.mp I0
  obtain ⟨p, _, H⟩ := HasUnitMulPowIrreducibleFactorization.of_ufd_of_unique_irreducible h₁ h₂
  

Proof state:
case neg.intro.intro.intro.intro
R✝ : Type u_1
R : Type u
inst✝² : CommRing R
inst✝¹ : IsDomain R
inst✝ : UniqueFactorizationMonoid R
h₁ : ∃ p, Irreducible p
h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q
I : Ideal R
I0 : ¬I = ⊥
x : R
hxI : x ∈ I
hx0 : x ≠ 0
p : R
left✝ : Irreducible p
H : ∀ {x : R}, x ≠ 0 → ∃ n, Associated (p ^ n) x
⊢ Submodule.IsPrincipal I

Next tactic:
have ex : ∃ n : ℕ, p ^ n ∈ I := by
    obtain ⟨n, u, rfl⟩ := H hx0
    refine' ⟨n, _⟩
    simpa only [Units.mul_inv_cancel_right] using I.mul_mem_right (↑u⁻¹) hxI
theorem aux_pid_of_ufd_of_unique_irreducible (R : Type u) [CommRing R] [IsDomain R]
    [UniqueFactorizationMonoid R] (h₁ : ∃ p : R, Irreducible p)
    (h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q) :
    IsPrincipalIdealRing R := by
  constructor
  intro I
  by_cases I0 : I = ⊥
  · rw [I0]
    use 0
    simp only [Set.singleton_zero, Submodule.span_zero]
  obtain ⟨x, hxI, hx0⟩ : ∃ x ∈ I, x ≠ (0 : R) := I.ne_bot_iff.mp I0
  obtain ⟨p, _, H⟩ := HasUnitMulPowIrreducibleFactorization.of_ufd_of_unique_irreducible h₁ h₂
  have ex : ∃ n : ℕ, p ^ n ∈ I := by
    

Proof state:
R✝ : Type u_1
R : Type u
inst✝² : CommRing R
inst✝¹ : IsDomain R
inst✝ : UniqueFactorizationMonoid R
h₁ : ∃ p, Irreducible p
h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q
I : Ideal R
I0 : ¬I = ⊥
x : R
hxI : x ∈ I
hx0 : x ≠ 0
p : R
left✝ : Irreducible p
H : ∀ {x : R}, x ≠ 0 → ∃ n, Associated (p ^ n) x
⊢ ∃ n, p ^ n ∈ I

Next tactic:
obtain ⟨n, u, rfl⟩ := H hx0
theorem aux_pid_of_ufd_of_unique_irreducible (R : Type u) [CommRing R] [IsDomain R]
    [UniqueFactorizationMonoid R] (h₁ : ∃ p : R, Irreducible p)
    (h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q) :
    IsPrincipalIdealRing R := by
  constructor
  intro I
  by_cases I0 : I = ⊥
  · rw [I0]
    use 0
    simp only [Set.singleton_zero, Submodule.span_zero]
  obtain ⟨x, hxI, hx0⟩ : ∃ x ∈ I, x ≠ (0 : R) := I.ne_bot_iff.mp I0
  obtain ⟨p, _, H⟩ := HasUnitMulPowIrreducibleFactorization.of_ufd_of_unique_irreducible h₁ h₂
  have ex : ∃ n : ℕ, p ^ n ∈ I := by
    obtain ⟨n, u, rfl⟩ := H hx0
    

Proof state:
case intro.intro
R✝ : Type u_1
R : Type u
inst✝² : CommRing R
inst✝¹ : IsDomain R
inst✝ : UniqueFactorizationMonoid R
h₁ : ∃ p, Irreducible p
h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q
I : Ideal R
I0 : ¬I = ⊥
p : R
left✝ : Irreducible p
H : ∀ {x : R}, x ≠ 0 → ∃ n, Associated (p ^ n) x
n : ℕ
u : Rˣ
hxI : p ^ n * ↑u ∈ I
hx0 : p ^ n * ↑u ≠ 0
⊢ ∃ n, p ^ n ∈ I

Next tactic:
refine' ⟨n, _⟩
theorem aux_pid_of_ufd_of_unique_irreducible (R : Type u) [CommRing R] [IsDomain R]
    [UniqueFactorizationMonoid R] (h₁ : ∃ p : R, Irreducible p)
    (h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q) :
    IsPrincipalIdealRing R := by
  constructor
  intro I
  by_cases I0 : I = ⊥
  · rw [I0]
    use 0
    simp only [Set.singleton_zero, Submodule.span_zero]
  obtain ⟨x, hxI, hx0⟩ : ∃ x ∈ I, x ≠ (0 : R) := I.ne_bot_iff.mp I0
  obtain ⟨p, _, H⟩ := HasUnitMulPowIrreducibleFactorization.of_ufd_of_unique_irreducible h₁ h₂
  have ex : ∃ n : ℕ, p ^ n ∈ I := by
    obtain ⟨n, u, rfl⟩ := H hx0
    refine' ⟨n, _⟩
    

Proof state:
case intro.intro
R✝ : Type u_1
R : Type u
inst✝² : CommRing R
inst✝¹ : IsDomain R
inst✝ : UniqueFactorizationMonoid R
h₁ : ∃ p, Irreducible p
h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q
I : Ideal R
I0 : ¬I = ⊥
p : R
left✝ : Irreducible p
H : ∀ {x : R}, x ≠ 0 → ∃ n, Associated (p ^ n) x
n : ℕ
u : Rˣ
hxI : p ^ n * ↑u ∈ I
hx0 : p ^ n * ↑u ≠ 0
⊢ p ^ n ∈ I

Next tactic:
simpa only [Units.mul_inv_cancel_right] using I.mul_mem_right (↑u⁻¹) hxI
theorem aux_pid_of_ufd_of_unique_irreducible (R : Type u) [CommRing R] [IsDomain R]
    [UniqueFactorizationMonoid R] (h₁ : ∃ p : R, Irreducible p)
    (h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q) :
    IsPrincipalIdealRing R := by
  constructor
  intro I
  by_cases I0 : I = ⊥
  · rw [I0]
    use 0
    simp only [Set.singleton_zero, Submodule.span_zero]
  obtain ⟨x, hxI, hx0⟩ : ∃ x ∈ I, x ≠ (0 : R) := I.ne_bot_iff.mp I0
  obtain ⟨p, _, H⟩ := HasUnitMulPowIrreducibleFactorization.of_ufd_of_unique_irreducible h₁ h₂
  have ex : ∃ n : ℕ, p ^ n ∈ I := by
    obtain ⟨n, u, rfl⟩ := H hx0
    refine' ⟨n, _⟩
    simpa only [Units.mul_inv_cancel_right] using I.mul_mem_right (↑u⁻¹) hxI
  

Proof state:
case neg.intro.intro.intro.intro
R✝ : Type u_1
R : Type u
inst✝² : CommRing R
inst✝¹ : IsDomain R
inst✝ : UniqueFactorizationMonoid R
h₁ : ∃ p, Irreducible p
h₂ : ∀ ⦃p q : R⦄, Irreducible p → Irreducible q → Associated p q
I : Ideal R
I0 : ¬I = ⊥
x : R
hxI : x ∈ I
hx0 : x ≠ 0
p : R
left✝ : Irreducible p
H : ∀ {x : R}, x ≠ 0 → ∃ n, Associated (p ^ n) x
ex : ∃ n, p ^ n ∈ I
⊢ Submodule.IsPrincipal I

Next tactic:
constructor