l3lab/ntp-mathlib huggingface dataset:
theorem coprime_classification :
    PythagoreanTriple x y z ∧ Int.gcd x y = 1 ↔
      ∃ m n,
        (x = m ^ 2 - n ^ 2 ∧ y = 2 * m * n ∨ x = 2 * m * n ∧ y = m ^ 2 - n ^ 2) ∧
          (z = m ^ 2 + n ^ 2 ∨ z = -(m ^ 2 + n ^ 2)) ∧
            Int.gcd m n = 1 ∧ (m % 2 = 0 ∧ n % 2 = 1 ∨ m % 2 = 1 ∧ n % 2 = 0) := by
  clear h -- porting note: don't want this variable, but can't use `include` / `omit`
  constructor
  · intro h
    obtain ⟨m, n, H⟩ := h.left.isPrimitiveClassified_of_coprime h.right
    use m, n
    rcases H with ⟨⟨rfl, rfl⟩ | ⟨rfl, rfl⟩, co, pp⟩
    · refine' ⟨Or.inl ⟨rfl, rfl⟩, _, co, pp⟩
      have : z ^ 2 = (m ^ 2 + n ^ 2) ^ 2 := by
        rw [sq, ← h.left.eq]
        ring
      simpa using eq_or_eq_neg_of_sq_eq_sq _ _ this
    · refine' ⟨Or.inr ⟨rfl, rfl⟩, _, co, pp⟩
      have : z ^ 2 = (m ^ 2 + n ^ 2) ^ 2 := by
        rw [sq, ← h.left.eq]
        ring
      simpa using eq_or_eq_neg_of_sq_eq_sq _ _ this
  · delta PythagoreanTriple
    rintro ⟨m, n, ⟨rfl, rfl⟩ | ⟨rfl, rfl⟩, rfl | rfl, co, pp⟩ <;>
      first
      | 

Proof state:
case mpr.intro.intro.intro.inl.intro.intro.inl.intro
m n : ℤ
co : Int.gcd m n = 1
pp : m % 2 = 0 ∧ n % 2 = 1 ∨ m % 2 = 1 ∧ n % 2 = 0
⊢ (m ^ 2 - n ^ 2) * (m ^ 2 - n ^ 2) + 2 * m * n * (2 * m * n) = (m ^ 2 + n ^ 2) * (m ^ 2 + n ^ 2) ∧
    Int.gcd (m ^ 2 - n ^ 2) (2 * m * n) = 1

Next tactic:
constructor
theorem coprime_classification :
    PythagoreanTriple x y z ∧ Int.gcd x y = 1 ↔
      ∃ m n,
        (x = m ^ 2 - n ^ 2 ∧ y = 2 * m * n ∨ x = 2 * m * n ∧ y = m ^ 2 - n ^ 2) ∧
          (z = m ^ 2 + n ^ 2 ∨ z = -(m ^ 2 + n ^ 2)) ∧
            Int.gcd m n = 1 ∧ (m % 2 = 0 ∧ n % 2 = 1 ∨ m % 2 = 1 ∧ n % 2 = 0) := by
  clear h -- porting note: don't want this variable, but can't use `include` / `omit`
  constructor
  · intro h
    obtain ⟨m, n, H⟩ := h.left.isPrimitiveClassified_of_coprime h.right
    use m, n
    rcases H with ⟨⟨rfl, rfl⟩ | ⟨rfl, rfl⟩, co, pp⟩
    · refine' ⟨Or.inl ⟨rfl, rfl⟩, _, co, pp⟩
      have : z ^ 2 = (m ^ 2 + n ^ 2) ^ 2 := by
        rw [sq, ← h.left.eq]
        ring
      simpa using eq_or_eq_neg_of_sq_eq_sq _ _ this
    · refine' ⟨Or.inr ⟨rfl, rfl⟩, _, co, pp⟩
      have : z ^ 2 = (m ^ 2 + n ^ 2) ^ 2 := by
        rw [sq, ← h.left.eq]
        ring
      simpa using eq_or_eq_neg_of_sq_eq_sq _ _ this
  · delta PythagoreanTriple
    rintro ⟨m, n, ⟨rfl, rfl⟩ | ⟨rfl, rfl⟩, rfl | rfl, co, pp⟩ <;>
      first
      | constructor; 

Proof state:
case mpr.intro.intro.intro.inl.intro.intro.inl.intro.left
m n : ℤ
co : Int.gcd m n = 1
pp : m % 2 = 0 ∧ n % 2 = 1 ∨ m % 2 = 1 ∧ n % 2 = 0
⊢ (m ^ 2 - n ^ 2) * (m ^ 2 - n ^ 2) + 2 * m * n * (2 * m * n) = (m ^ 2 + n ^ 2) * (m ^ 2 + n ^ 2)
case mpr.intro.intro.intro.inl.intro.intro.inl.intro.right
m n : ℤ
co : Int.gcd m n = 1
pp : m % 2 = 0 ∧ n % 2 = 1 ∨ m % 2 = 1 ∧ n % 2 = 0
⊢ Int.gcd (m ^ 2 - n ^ 2) (2 * m * n) = 1

Next tactic:
ring
theorem coprime_classification :
    PythagoreanTriple x y z ∧ Int.gcd x y = 1 ↔
      ∃ m n,
        (x = m ^ 2 - n ^ 2 ∧ y = 2 * m * n ∨ x = 2 * m * n ∧ y = m ^ 2 - n ^ 2) ∧
          (z = m ^ 2 + n ^ 2 ∨ z = -(m ^ 2 + n ^ 2)) ∧
            Int.gcd m n = 1 ∧ (m % 2 = 0 ∧ n % 2 = 1 ∨ m % 2 = 1 ∧ n % 2 = 0) := by
  clear h -- porting note: don't want this variable, but can't use `include` / `omit`
  constructor
  · intro h
    obtain ⟨m, n, H⟩ := h.left.isPrimitiveClassified_of_coprime h.right
    use m, n
    rcases H with ⟨⟨rfl, rfl⟩ | ⟨rfl, rfl⟩, co, pp⟩
    · refine' ⟨Or.inl ⟨rfl, rfl⟩, _, co, pp⟩
      have : z ^ 2 = (m ^ 2 + n ^ 2) ^ 2 := by
        rw [sq, ← h.left.eq]
        ring
      simpa using eq_or_eq_neg_of_sq_eq_sq _ _ this
    · refine' ⟨Or.inr ⟨rfl, rfl⟩, _, co, pp⟩
      have : z ^ 2 = (m ^ 2 + n ^ 2) ^ 2 := by
        rw [sq, ← h.left.eq]
        ring
      simpa using eq_or_eq_neg_of_sq_eq_sq _ _ this
  · delta PythagoreanTriple
    rintro ⟨m, n, ⟨rfl, rfl⟩ | ⟨rfl, rfl⟩, rfl | rfl, co, pp⟩ <;>
      first
      | constructor; ring; 

Proof state:
case mpr.intro.intro.intro.inl.intro.intro.inl.intro.right
m n : ℤ
co : Int.gcd m n = 1
pp : m % 2 = 0 ∧ n % 2 = 1 ∨ m % 2 = 1 ∧ n % 2 = 0
⊢ Int.gcd (m ^ 2 - n ^ 2) (2 * m * n) = 1

Next tactic:
exact coprime_sq_sub_mul co pp
theorem coprime_classification :
    PythagoreanTriple x y z ∧ Int.gcd x y = 1 ↔
      ∃ m n,
        (x = m ^ 2 - n ^ 2 ∧ y = 2 * m * n ∨ x = 2 * m * n ∧ y = m ^ 2 - n ^ 2) ∧
          (z = m ^ 2 + n ^ 2 ∨ z = -(m ^ 2 + n ^ 2)) ∧
            Int.gcd m n = 1 ∧ (m % 2 = 0 ∧ n % 2 = 1 ∨ m % 2 = 1 ∧ n % 2 = 0) := by
  clear h -- porting note: don't want this variable, but can't use `include` / `omit`
  constructor
  · intro h
    obtain ⟨m, n, H⟩ := h.left.isPrimitiveClassified_of_coprime h.right
    use m, n
    rcases H with ⟨⟨rfl, rfl⟩ | ⟨rfl, rfl⟩, co, pp⟩
    · refine' ⟨Or.inl ⟨rfl, rfl⟩, _, co, pp⟩
      have : z ^ 2 = (m ^ 2 + n ^ 2) ^ 2 := by
        rw [sq, ← h.left.eq]
        ring
      simpa using eq_or_eq_neg_of_sq_eq_sq _ _ this
    · refine' ⟨Or.inr ⟨rfl, rfl⟩, _, co, pp⟩
      have : z ^ 2 = (m ^ 2 + n ^ 2) ^ 2 := by
        rw [sq, ← h.left.eq]
        ring
      simpa using eq_or_eq_neg_of_sq_eq_sq _ _ this
  · delta PythagoreanTriple
    rintro ⟨m, n, ⟨rfl, rfl⟩ | ⟨rfl, rfl⟩, rfl | rfl, co, pp⟩ <;>
      

Proof state:
case mpr.intro.intro.intro.inl.intro.intro.inr.intro
m n : ℤ
co : Int.gcd m n = 1
pp : m % 2 = 0 ∧ n % 2 = 1 ∨ m % 2 = 1 ∧ n % 2 = 0
⊢ (m ^ 2 - n ^ 2) * (m ^ 2 - n ^ 2) + 2 * m * n * (2 * m * n) = -(m ^ 2 + n ^ 2) * -(m ^ 2 + n ^ 2) ∧
    Int.gcd (m ^ 2 - n ^ 2) (2 * m * n) = 1

Next tactic:
first
      | constructor; ring; exact coprime_sq_sub_mul co pp
      | constructor; ring; rw [Int.gcd_comm]; exact coprime_sq_sub_mul co pp
theorem coprime_classification :
    PythagoreanTriple x y z ∧ Int.gcd x y = 1 ↔
      ∃ m n,
        (x = m ^ 2 - n ^ 2 ∧ y = 2 * m * n ∨ x = 2 * m * n ∧ y = m ^ 2 - n ^ 2) ∧
          (z = m ^ 2 + n ^ 2 ∨ z = -(m ^ 2 + n ^ 2)) ∧
            Int.gcd m n = 1 ∧ (m % 2 = 0 ∧ n % 2 = 1 ∨ m % 2 = 1 ∧ n % 2 = 0) := by
  clear h -- porting note: don't want this variable, but can't use `include` / `omit`
  constructor
  · intro h
    obtain ⟨m, n, H⟩ := h.left.isPrimitiveClassified_of_coprime h.right
    use m, n
    rcases H with ⟨⟨rfl, rfl⟩ | ⟨rfl, rfl⟩, co, pp⟩
    · refine' ⟨Or.inl ⟨rfl, rfl⟩, _, co, pp⟩
      have : z ^ 2 = (m ^ 2 + n ^ 2) ^ 2 := by
        rw [sq, ← h.left.eq]
        ring
      simpa using eq_or_eq_neg_of_sq_eq_sq _ _ this
    · refine' ⟨Or.inr ⟨rfl, rfl⟩, _, co, pp⟩
      have : z ^ 2 = (m ^ 2 + n ^ 2) ^ 2 := by
        rw [sq, ← h.left.eq]
        ring
      simpa using eq_or_eq_neg_of_sq_eq_sq _ _ this
  · delta PythagoreanTriple
    rintro ⟨m, n, ⟨rfl, rfl⟩ | ⟨rfl, rfl⟩, rfl | rfl, co, pp⟩ <;>
      first
      | 

Proof state:
case mpr.intro.intro.intro.inl.intro.intro.inr.intro
m n : ℤ
co : Int.gcd m n = 1
pp : m % 2 = 0 ∧ n % 2 = 1 ∨ m % 2 = 1 ∧ n % 2 = 0
⊢ (m ^ 2 - n ^ 2) * (m ^ 2 - n ^ 2) + 2 * m * n * (2 * m * n) = -(m ^ 2 + n ^ 2) * -(m ^ 2 + n ^ 2) ∧
    Int.gcd (m ^ 2 - n ^ 2) (2 * m * n) = 1

Next tactic:
constructor
theorem coprime_classification :
    PythagoreanTriple x y z ∧ Int.gcd x y = 1 ↔
      ∃ m n,
        (x = m ^ 2 - n ^ 2 ∧ y = 2 * m * n ∨ x = 2 * m * n ∧ y = m ^ 2 - n ^ 2) ∧
          (z = m ^ 2 + n ^ 2 ∨ z = -(m ^ 2 + n ^ 2)) ∧
            Int.gcd m n = 1 ∧ (m % 2 = 0 ∧ n % 2 = 1 ∨ m % 2 = 1 ∧ n % 2 = 0) := by
  clear h -- porting note: don't want this variable, but can't use `include` / `omit`
  constructor
  · intro h
    obtain ⟨m, n, H⟩ := h.left.isPrimitiveClassified_of_coprime h.right
    use m, n
    rcases H with ⟨⟨rfl, rfl⟩ | ⟨rfl, rfl⟩, co, pp⟩
    · refine' ⟨Or.inl ⟨rfl, rfl⟩, _, co, pp⟩
      have : z ^ 2 = (m ^ 2 + n ^ 2) ^ 2 := by
        rw [sq, ← h.left.eq]
        ring
      simpa using eq_or_eq_neg_of_sq_eq_sq _ _ this
    · refine' ⟨Or.inr ⟨rfl, rfl⟩, _, co, pp⟩
      have : z ^ 2 = (m ^ 2 + n ^ 2) ^ 2 := by
        rw [sq, ← h.left.eq]
        ring
      simpa using eq_or_eq_neg_of_sq_eq_sq _ _ this
  · delta PythagoreanTriple
    rintro ⟨m, n, ⟨rfl, rfl⟩ | ⟨rfl, rfl⟩, rfl | rfl, co, pp⟩ <;>
      first
      | constructor; 

Proof state:
case mpr.intro.intro.intro.inl.intro.intro.inr.intro.left
m n : ℤ
co : Int.gcd m n = 1
pp : m % 2 = 0 ∧ n % 2 = 1 ∨ m % 2 = 1 ∧ n % 2 = 0
⊢ (m ^ 2 - n ^ 2) * (m ^ 2 - n ^ 2) + 2 * m * n * (2 * m * n) = -(m ^ 2 + n ^ 2) * -(m ^ 2 + n ^ 2)
case mpr.intro.intro.intro.inl.intro.intro.inr.intro.right
m n : ℤ
co : Int.gcd m n = 1
pp : m % 2 = 0 ∧ n % 2 = 1 ∨ m % 2 = 1 ∧ n % 2 = 0
⊢ Int.gcd (m ^ 2 - n ^ 2) (2 * m * n) = 1

Next tactic:
ring
theorem coprime_classification :
    PythagoreanTriple x y z ∧ Int.gcd x y = 1 ↔
      ∃ m n,
        (x = m ^ 2 - n ^ 2 ∧ y = 2 * m * n ∨ x = 2 * m * n ∧ y = m ^ 2 - n ^ 2) ∧
          (z = m ^ 2 + n ^ 2 ∨ z = -(m ^ 2 + n ^ 2)) ∧
            Int.gcd m n = 1 ∧ (m % 2 = 0 ∧ n % 2 = 1 ∨ m % 2 = 1 ∧ n % 2 = 0) := by
  clear h -- porting note: don't want this variable, but can't use `include` / `omit`
  constructor
  · intro h
    obtain ⟨m, n, H⟩ := h.left.isPrimitiveClassified_of_coprime h.right
    use m, n
    rcases H with ⟨⟨rfl, rfl⟩ | ⟨rfl, rfl⟩, co, pp⟩
    · refine' ⟨Or.inl ⟨rfl, rfl⟩, _, co, pp⟩
      have : z ^ 2 = (m ^ 2 + n ^ 2) ^ 2 := by
        rw [sq, ← h.left.eq]
        ring
      simpa using eq_or_eq_neg_of_sq_eq_sq _ _ this
    · refine' ⟨Or.inr ⟨rfl, rfl⟩, _, co, pp⟩
      have : z ^ 2 = (m ^ 2 + n ^ 2) ^ 2 := by
        rw [sq, ← h.left.eq]
        ring
      simpa using eq_or_eq_neg_of_sq_eq_sq _ _ this
  · delta PythagoreanTriple
    rintro ⟨m, n, ⟨rfl, rfl⟩ | ⟨rfl, rfl⟩, rfl | rfl, co, pp⟩ <;>
      first
      | constructor; ring; 

Proof state:
case mpr.intro.intro.intro.inl.intro.intro.inr.intro.right
m n : ℤ
co : Int.gcd m n = 1
pp : m % 2 = 0 ∧ n % 2 = 1 ∨ m % 2 = 1 ∧ n % 2 = 0
⊢ Int.gcd (m ^ 2 - n ^ 2) (2 * m * n) = 1

Next tactic:
exact coprime_sq_sub_mul co pp
theorem coprime_classification :
    PythagoreanTriple x y z ∧ Int.gcd x y = 1 ↔
      ∃ m n,
        (x = m ^ 2 - n ^ 2 ∧ y = 2 * m * n ∨ x = 2 * m * n ∧ y = m ^ 2 - n ^ 2) ∧
          (z = m ^ 2 + n ^ 2 ∨ z = -(m ^ 2 + n ^ 2)) ∧
            Int.gcd m n = 1 ∧ (m % 2 = 0 ∧ n % 2 = 1 ∨ m % 2 = 1 ∧ n % 2 = 0) := by
  clear h -- porting note: don't want this variable, but can't use `include` / `omit`
  constructor
  · intro h
    obtain ⟨m, n, H⟩ := h.left.isPrimitiveClassified_of_coprime h.right
    use m, n
    rcases H with ⟨⟨rfl, rfl⟩ | ⟨rfl, rfl⟩, co, pp⟩
    · refine' ⟨Or.inl ⟨rfl, rfl⟩, _, co, pp⟩
      have : z ^ 2 = (m ^ 2 + n ^ 2) ^ 2 := by
        rw [sq, ← h.left.eq]
        ring
      simpa using eq_or_eq_neg_of_sq_eq_sq _ _ this
    · refine' ⟨Or.inr ⟨rfl, rfl⟩, _, co, pp⟩
      have : z ^ 2 = (m ^ 2 + n ^ 2) ^ 2 := by
        rw [sq, ← h.left.eq]
        ring
      simpa using eq_or_eq_neg_of_sq_eq_sq _ _ this
  · delta PythagoreanTriple
    rintro ⟨m, n, ⟨rfl, rfl⟩ | ⟨rfl, rfl⟩, rfl | rfl, co, pp⟩ <;>
      

Proof state:
case mpr.intro.intro.intro.inr.intro.intro.inl.intro
m n : ℤ
co : Int.gcd m n = 1
pp : m % 2 = 0 ∧ n % 2 = 1 ∨ m % 2 = 1 ∧ n % 2 = 0
⊢ 2 * m * n * (2 * m * n) + (m ^ 2 - n ^ 2) * (m ^ 2 - n ^ 2) = (m ^ 2 + n ^ 2) * (m ^ 2 + n ^ 2) ∧
    Int.gcd (2 * m * n) (m ^ 2 - n ^ 2) = 1

Next tactic:
first
      | constructor; ring; exact coprime_sq_sub_mul co pp
      | constructor; ring; rw [Int.gcd_comm]; exact coprime_sq_sub_mul co pp
theorem coprime_classification :
    PythagoreanTriple x y z ∧ Int.gcd x y = 1 ↔
      ∃ m n,
        (x = m ^ 2 - n ^ 2 ∧ y = 2 * m * n ∨ x = 2 * m * n ∧ y = m ^ 2 - n ^ 2) ∧
          (z = m ^ 2 + n ^ 2 ∨ z = -(m ^ 2 + n ^ 2)) ∧
            Int.gcd m n = 1 ∧ (m % 2 = 0 ∧ n % 2 = 1 ∨ m % 2 = 1 ∧ n % 2 = 0) := by
  clear h -- porting note: don't want this variable, but can't use `include` / `omit`
  constructor
  · intro h
    obtain ⟨m, n, H⟩ := h.left.isPrimitiveClassified_of_coprime h.right
    use m, n
    rcases H with ⟨⟨rfl, rfl⟩ | ⟨rfl, rfl⟩, co, pp⟩
    · refine' ⟨Or.inl ⟨rfl, rfl⟩, _, co, pp⟩
      have : z ^ 2 = (m ^ 2 + n ^ 2) ^ 2 := by
        rw [sq, ← h.left.eq]
        ring
      simpa using eq_or_eq_neg_of_sq_eq_sq _ _ this
    · refine' ⟨Or.inr ⟨rfl, rfl⟩, _, co, pp⟩
      have : z ^ 2 = (m ^ 2 + n ^ 2) ^ 2 := by
        rw [sq, ← h.left.eq]
        ring
      simpa using eq_or_eq_neg_of_sq_eq_sq _ _ this
  · delta PythagoreanTriple
    rintro ⟨m, n, ⟨rfl, rfl⟩ | ⟨rfl, rfl⟩, rfl | rfl, co, pp⟩ <;>
      first
      | 

Proof state:
case mpr.intro.intro.intro.inr.intro.intro.inl.intro
m n : ℤ
co : Int.gcd m n = 1
pp : m % 2 = 0 ∧ n % 2 = 1 ∨ m % 2 = 1 ∧ n % 2 = 0
⊢ 2 * m * n * (2 * m * n) + (m ^ 2 - n ^ 2) * (m ^ 2 - n ^ 2) = (m ^ 2 + n ^ 2) * (m ^ 2 + n ^ 2) ∧
    Int.gcd (2 * m * n) (m ^ 2 - n ^ 2) = 1

Next tactic:
constructor
theorem coprime_classification :
    PythagoreanTriple x y z ∧ Int.gcd x y = 1 ↔
      ∃ m n,
        (x = m ^ 2 - n ^ 2 ∧ y = 2 * m * n ∨ x = 2 * m * n ∧ y = m ^ 2 - n ^ 2) ∧
          (z = m ^ 2 + n ^ 2 ∨ z = -(m ^ 2 + n ^ 2)) ∧
            Int.gcd m n = 1 ∧ (m % 2 = 0 ∧ n % 2 = 1 ∨ m % 2 = 1 ∧ n % 2 = 0) := by
  clear h -- porting note: don't want this variable, but can't use `include` / `omit`
  constructor
  · intro h
    obtain ⟨m, n, H⟩ := h.left.isPrimitiveClassified_of_coprime h.right
    use m, n
    rcases H with ⟨⟨rfl, rfl⟩ | ⟨rfl, rfl⟩, co, pp⟩
    · refine' ⟨Or.inl ⟨rfl, rfl⟩, _, co, pp⟩
      have : z ^ 2 = (m ^ 2 + n ^ 2) ^ 2 := by
        rw [sq, ← h.left.eq]
        ring
      simpa using eq_or_eq_neg_of_sq_eq_sq _ _ this
    · refine' ⟨Or.inr ⟨rfl, rfl⟩, _, co, pp⟩
      have : z ^ 2 = (m ^ 2 + n ^ 2) ^ 2 := by
        rw [sq, ← h.left.eq]
        ring
      simpa using eq_or_eq_neg_of_sq_eq_sq _ _ this
  · delta PythagoreanTriple
    rintro ⟨m, n, ⟨rfl, rfl⟩ | ⟨rfl, rfl⟩, rfl | rfl, co, pp⟩ <;>
      first
      | constructor; 

Proof state:
case mpr.intro.intro.intro.inr.intro.intro.inl.intro.left
m n : ℤ
co : Int.gcd m n = 1
pp : m % 2 = 0 ∧ n % 2 = 1 ∨ m % 2 = 1 ∧ n % 2 = 0
⊢ 2 * m * n * (2 * m * n) + (m ^ 2 - n ^ 2) * (m ^ 2 - n ^ 2) = (m ^ 2 + n ^ 2) * (m ^ 2 + n ^ 2)
case mpr.intro.intro.intro.inr.intro.intro.inl.intro.right
m n : ℤ
co : Int.gcd m n = 1
pp : m % 2 = 0 ∧ n % 2 = 1 ∨ m % 2 = 1 ∧ n % 2 = 0
⊢ Int.gcd (2 * m * n) (m ^ 2 - n ^ 2) = 1

Next tactic:
ring
theorem coprime_classification :
    PythagoreanTriple x y z ∧ Int.gcd x y = 1 ↔
      ∃ m n,
        (x = m ^ 2 - n ^ 2 ∧ y = 2 * m * n ∨ x = 2 * m * n ∧ y = m ^ 2 - n ^ 2) ∧
          (z = m ^ 2 + n ^ 2 ∨ z = -(m ^ 2 + n ^ 2)) ∧
            Int.gcd m n = 1 ∧ (m % 2 = 0 ∧ n % 2 = 1 ∨ m % 2 = 1 ∧ n % 2 = 0) := by
  clear h -- porting note: don't want this variable, but can't use `include` / `omit`
  constructor
  · intro h
    obtain ⟨m, n, H⟩ := h.left.isPrimitiveClassified_of_coprime h.right
    use m, n
    rcases H with ⟨⟨rfl, rfl⟩ | ⟨rfl, rfl⟩, co, pp⟩
    · refine' ⟨Or.inl ⟨rfl, rfl⟩, _, co, pp⟩
      have : z ^ 2 = (m ^ 2 + n ^ 2) ^ 2 := by
        rw [sq, ← h.left.eq]
        ring
      simpa using eq_or_eq_neg_of_sq_eq_sq _ _ this
    · refine' ⟨Or.inr ⟨rfl, rfl⟩, _, co, pp⟩
      have : z ^ 2 = (m ^ 2 + n ^ 2) ^ 2 := by
        rw [sq, ← h.left.eq]
        ring
      simpa using eq_or_eq_neg_of_sq_eq_sq _ _ this
  · delta PythagoreanTriple
    rintro ⟨m, n, ⟨rfl, rfl⟩ | ⟨rfl, rfl⟩, rfl | rfl, co, pp⟩ <;>
      first
      | constructor; ring; 

Proof state:
case mpr.intro.intro.intro.inr.intro.intro.inl.intro.right
m n : ℤ
co : Int.gcd m n = 1
pp : m % 2 = 0 ∧ n % 2 = 1 ∨ m % 2 = 1 ∧ n % 2 = 0
⊢ Int.gcd (2 * m * n) (m ^ 2 - n ^ 2) = 1

Next tactic:
exact coprime_sq_sub_mul co pp
theorem coprime_classification :
    PythagoreanTriple x y z ∧ Int.gcd x y = 1 ↔
      ∃ m n,
        (x = m ^ 2 - n ^ 2 ∧ y = 2 * m * n ∨ x = 2 * m * n ∧ y = m ^ 2 - n ^ 2) ∧
          (z = m ^ 2 + n ^ 2 ∨ z = -(m ^ 2 + n ^ 2)) ∧
            Int.gcd m n = 1 ∧ (m % 2 = 0 ∧ n % 2 = 1 ∨ m % 2 = 1 ∧ n % 2 = 0) := by
  clear h -- porting note: don't want this variable, but can't use `include` / `omit`
  constructor
  · intro h
    obtain ⟨m, n, H⟩ := h.left.isPrimitiveClassified_of_coprime h.right
    use m, n
    rcases H with ⟨⟨rfl, rfl⟩ | ⟨rfl, rfl⟩, co, pp⟩
    · refine' ⟨Or.inl ⟨rfl, rfl⟩, _, co, pp⟩
      have : z ^ 2 = (m ^ 2 + n ^ 2) ^ 2 := by
        rw [sq, ← h.left.eq]
        ring
      simpa using eq_or_eq_neg_of_sq_eq_sq _ _ this
    · refine' ⟨Or.inr ⟨rfl, rfl⟩, _, co, pp⟩
      have : z ^ 2 = (m ^ 2 + n ^ 2) ^ 2 := by
        rw [sq, ← h.left.eq]
        ring
      simpa using eq_or_eq_neg_of_sq_eq_sq _ _ this
  · delta PythagoreanTriple
    rintro ⟨m, n, ⟨rfl, rfl⟩ | ⟨rfl, rfl⟩, rfl | rfl, co, pp⟩ <;>
      first
      | constructor; ring; exact coprime_sq_sub_mul co pp
      | 

Proof state:
case mpr.intro.intro.intro.inr.intro.intro.inl.intro
m n : ℤ
co : Int.gcd m n = 1
pp : m % 2 = 0 ∧ n % 2 = 1 ∨ m % 2 = 1 ∧ n % 2 = 0
⊢ 2 * m * n * (2 * m * n) + (m ^ 2 - n ^ 2) * (m ^ 2 - n ^ 2) = (m ^ 2 + n ^ 2) * (m ^ 2 + n ^ 2) ∧
    Int.gcd (2 * m * n) (m ^ 2 - n ^ 2) = 1

Next tactic:
constructor
theorem coprime_classification :
    PythagoreanTriple x y z ∧ Int.gcd x y = 1 ↔
      ∃ m n,
        (x = m ^ 2 - n ^ 2 ∧ y = 2 * m * n ∨ x = 2 * m * n ∧ y = m ^ 2 - n ^ 2) ∧
          (z = m ^ 2 + n ^ 2 ∨ z = -(m ^ 2 + n ^ 2)) ∧
            Int.gcd m n = 1 ∧ (m % 2 = 0 ∧ n % 2 = 1 ∨ m % 2 = 1 ∧ n % 2 = 0) := by
  clear h -- porting note: don't want this variable, but can't use `include` / `omit`
  constructor
  · intro h
    obtain ⟨m, n, H⟩ := h.left.isPrimitiveClassified_of_coprime h.right
    use m, n
    rcases H with ⟨⟨rfl, rfl⟩ | ⟨rfl, rfl⟩, co, pp⟩
    · refine' ⟨Or.inl ⟨rfl, rfl⟩, _, co, pp⟩
      have : z ^ 2 = (m ^ 2 + n ^ 2) ^ 2 := by
        rw [sq, ← h.left.eq]
        ring
      simpa using eq_or_eq_neg_of_sq_eq_sq _ _ this
    · refine' ⟨Or.inr ⟨rfl, rfl⟩, _, co, pp⟩
      have : z ^ 2 = (m ^ 2 + n ^ 2) ^ 2 := by
        rw [sq, ← h.left.eq]
        ring
      simpa using eq_or_eq_neg_of_sq_eq_sq _ _ this
  · delta PythagoreanTriple
    rintro ⟨m, n, ⟨rfl, rfl⟩ | ⟨rfl, rfl⟩, rfl | rfl, co, pp⟩ <;>
      first
      | constructor; ring; exact coprime_sq_sub_mul co pp
      | constructor; 

Proof state:
case mpr.intro.intro.intro.inr.intro.intro.inl.intro.left
m n : ℤ
co : Int.gcd m n = 1
pp : m % 2 = 0 ∧ n % 2 = 1 ∨ m % 2 = 1 ∧ n % 2 = 0
⊢ 2 * m * n * (2 * m * n) + (m ^ 2 - n ^ 2) * (m ^ 2 - n ^ 2) = (m ^ 2 + n ^ 2) * (m ^ 2 + n ^ 2)
case mpr.intro.intro.intro.inr.intro.intro.inl.intro.right
m n : ℤ
co : Int.gcd m n = 1
pp : m % 2 = 0 ∧ n % 2 = 1 ∨ m % 2 = 1 ∧ n % 2 = 0
⊢ Int.gcd (2 * m * n) (m ^ 2 - n ^ 2) = 1

Next tactic:
ring
theorem coprime_classification :
    PythagoreanTriple x y z ∧ Int.gcd x y = 1 ↔
      ∃ m n,
        (x = m ^ 2 - n ^ 2 ∧ y = 2 * m * n ∨ x = 2 * m * n ∧ y = m ^ 2 - n ^ 2) ∧
          (z = m ^ 2 + n ^ 2 ∨ z = -(m ^ 2 + n ^ 2)) ∧
            Int.gcd m n = 1 ∧ (m % 2 = 0 ∧ n % 2 = 1 ∨ m % 2 = 1 ∧ n % 2 = 0) := by
  clear h -- porting note: don't want this variable, but can't use `include` / `omit`
  constructor
  · intro h
    obtain ⟨m, n, H⟩ := h.left.isPrimitiveClassified_of_coprime h.right
    use m, n
    rcases H with ⟨⟨rfl, rfl⟩ | ⟨rfl, rfl⟩, co, pp⟩
    · refine' ⟨Or.inl ⟨rfl, rfl⟩, _, co, pp⟩
      have : z ^ 2 = (m ^ 2 + n ^ 2) ^ 2 := by
        rw [sq, ← h.left.eq]
        ring
      simpa using eq_or_eq_neg_of_sq_eq_sq _ _ this
    · refine' ⟨Or.inr ⟨rfl, rfl⟩, _, co, pp⟩
      have : z ^ 2 = (m ^ 2 + n ^ 2) ^ 2 := by
        rw [sq, ← h.left.eq]
        ring
      simpa using eq_or_eq_neg_of_sq_eq_sq _ _ this
  · delta PythagoreanTriple
    rintro ⟨m, n, ⟨rfl, rfl⟩ | ⟨rfl, rfl⟩, rfl | rfl, co, pp⟩ <;>
      first
      | constructor; ring; exact coprime_sq_sub_mul co pp
      | constructor; ring; 

Proof state:
case mpr.intro.intro.intro.inr.intro.intro.inl.intro.right
m n : ℤ
co : Int.gcd m n = 1
pp : m % 2 = 0 ∧ n % 2 = 1 ∨ m % 2 = 1 ∧ n % 2 = 0
⊢ Int.gcd (2 * m * n) (m ^ 2 - n ^ 2) = 1

Next tactic:
rw [Int.gcd_comm]
theorem coprime_classification :
    PythagoreanTriple x y z ∧ Int.gcd x y = 1 ↔
      ∃ m n,
        (x = m ^ 2 - n ^ 2 ∧ y = 2 * m * n ∨ x = 2 * m * n ∧ y = m ^ 2 - n ^ 2) ∧
          (z = m ^ 2 + n ^ 2 ∨ z = -(m ^ 2 + n ^ 2)) ∧
            Int.gcd m n = 1 ∧ (m % 2 = 0 ∧ n % 2 = 1 ∨ m % 2 = 1 ∧ n % 2 = 0) := by
  clear h -- porting note: don't want this variable, but can't use `include` / `omit`
  constructor
  · intro h
    obtain ⟨m, n, H⟩ := h.left.isPrimitiveClassified_of_coprime h.right
    use m, n
    rcases H with ⟨⟨rfl, rfl⟩ | ⟨rfl, rfl⟩, co, pp⟩
    · refine' ⟨Or.inl ⟨rfl, rfl⟩, _, co, pp⟩
      have : z ^ 2 = (m ^ 2 + n ^ 2) ^ 2 := by
        rw [sq, ← h.left.eq]
        ring
      simpa using eq_or_eq_neg_of_sq_eq_sq _ _ this
    · refine' ⟨Or.inr ⟨rfl, rfl⟩, _, co, pp⟩
      have : z ^ 2 = (m ^ 2 + n ^ 2) ^ 2 := by
        rw [sq, ← h.left.eq]
        ring
      simpa using eq_or_eq_neg_of_sq_eq_sq _ _ this
  · delta PythagoreanTriple
    rintro ⟨m, n, ⟨rfl, rfl⟩ | ⟨rfl, rfl⟩, rfl | rfl, co, pp⟩ <;>
      first
      | constructor; ring; exact coprime_sq_sub_mul co pp
      | constructor; ring; rw [Int.gcd_comm]; 

Proof state:
case mpr.intro.intro.intro.inr.intro.intro.inl.intro.right
m n : ℤ
co : Int.gcd m n = 1
pp : m % 2 = 0 ∧ n % 2 = 1 ∨ m % 2 = 1 ∧ n % 2 = 0
⊢ Int.gcd (m ^ 2 - n ^ 2) (2 * m * n) = 1

Next tactic:
exact coprime_sq_sub_mul co pp
theorem coprime_classification :
    PythagoreanTriple x y z ∧ Int.gcd x y = 1 ↔
      ∃ m n,
        (x = m ^ 2 - n ^ 2 ∧ y = 2 * m * n ∨ x = 2 * m * n ∧ y = m ^ 2 - n ^ 2) ∧
          (z = m ^ 2 + n ^ 2 ∨ z = -(m ^ 2 + n ^ 2)) ∧
            Int.gcd m n = 1 ∧ (m % 2 = 0 ∧ n % 2 = 1 ∨ m % 2 = 1 ∧ n % 2 = 0) := by
  clear h -- porting note: don't want this variable, but can't use `include` / `omit`
  constructor
  · intro h
    obtain ⟨m, n, H⟩ := h.left.isPrimitiveClassified_of_coprime h.right
    use m, n
    rcases H with ⟨⟨rfl, rfl⟩ | ⟨rfl, rfl⟩, co, pp⟩
    · refine' ⟨Or.inl ⟨rfl, rfl⟩, _, co, pp⟩
      have : z ^ 2 = (m ^ 2 + n ^ 2) ^ 2 := by
        rw [sq, ← h.left.eq]
        ring
      simpa using eq_or_eq_neg_of_sq_eq_sq _ _ this
    · refine' ⟨Or.inr ⟨rfl, rfl⟩, _, co, pp⟩
      have : z ^ 2 = (m ^ 2 + n ^ 2) ^ 2 := by
        rw [sq, ← h.left.eq]
        ring
      simpa using eq_or_eq_neg_of_sq_eq_sq _ _ this
  · delta PythagoreanTriple
    rintro ⟨m, n, ⟨rfl, rfl⟩ | ⟨rfl, rfl⟩, rfl | rfl, co, pp⟩ <;>
      

Proof state:
case mpr.intro.intro.intro.inr.intro.intro.inr.intro
m n : ℤ
co : Int.gcd m n = 1
pp : m % 2 = 0 ∧ n % 2 = 1 ∨ m % 2 = 1 ∧ n % 2 = 0
⊢ 2 * m * n * (2 * m * n) + (m ^ 2 - n ^ 2) * (m ^ 2 - n ^ 2) = -(m ^ 2 + n ^ 2) * -(m ^ 2 + n ^ 2) ∧
    Int.gcd (2 * m * n) (m ^ 2 - n ^ 2) = 1

Next tactic:
first
      | constructor; ring; exact coprime_sq_sub_mul co pp
      | constructor; ring; rw [Int.gcd_comm]; exact coprime_sq_sub_mul co pp
theorem coprime_classification :
    PythagoreanTriple x y z ∧ Int.gcd x y = 1 ↔
      ∃ m n,
        (x = m ^ 2 - n ^ 2 ∧ y = 2 * m * n ∨ x = 2 * m * n ∧ y = m ^ 2 - n ^ 2) ∧
          (z = m ^ 2 + n ^ 2 ∨ z = -(m ^ 2 + n ^ 2)) ∧
            Int.gcd m n = 1 ∧ (m % 2 = 0 ∧ n % 2 = 1 ∨ m % 2 = 1 ∧ n % 2 = 0) := by
  clear h -- porting note: don't want this variable, but can't use `include` / `omit`
  constructor
  · intro h
    obtain ⟨m, n, H⟩ := h.left.isPrimitiveClassified_of_coprime h.right
    use m, n
    rcases H with ⟨⟨rfl, rfl⟩ | ⟨rfl, rfl⟩, co, pp⟩
    · refine' ⟨Or.inl ⟨rfl, rfl⟩, _, co, pp⟩
      have : z ^ 2 = (m ^ 2 + n ^ 2) ^ 2 := by
        rw [sq, ← h.left.eq]
        ring
      simpa using eq_or_eq_neg_of_sq_eq_sq _ _ this
    · refine' ⟨Or.inr ⟨rfl, rfl⟩, _, co, pp⟩
      have : z ^ 2 = (m ^ 2 + n ^ 2) ^ 2 := by
        rw [sq, ← h.left.eq]
        ring
      simpa using eq_or_eq_neg_of_sq_eq_sq _ _ this
  · delta PythagoreanTriple
    rintro ⟨m, n, ⟨rfl, rfl⟩ | ⟨rfl, rfl⟩, rfl | rfl, co, pp⟩ <;>
      first
      | 

Proof state:
case mpr.intro.intro.intro.inr.intro.intro.inr.intro
m n : ℤ
co : Int.gcd m n = 1
pp : m % 2 = 0 ∧ n % 2 = 1 ∨ m % 2 = 1 ∧ n % 2 = 0
⊢ 2 * m * n * (2 * m * n) + (m ^ 2 - n ^ 2) * (m ^ 2 - n ^ 2) = -(m ^ 2 + n ^ 2) * -(m ^ 2 + n ^ 2) ∧
    Int.gcd (2 * m * n) (m ^ 2 - n ^ 2) = 1

Next tactic:
constructor