l3lab/ntp-mathlib huggingface dataset:
theorem exists_coprime_of_gcd_pos {a : ℤ√d} (hgcd : 0 < Int.gcd a.re a.im) :
    ∃ b : ℤ√d, a = ((Int.gcd a.re a.im : ℤ) : ℤ√d) * b ∧ IsCoprime b.re b.im := by
  

Proof state:
d : ℤ
a : ℤ√d
hgcd : 0 < Int.gcd a.re a.im
⊢ ∃ b, a = ↑↑(Int.gcd a.re a.im) * b ∧ IsCoprime b.re b.im

Next tactic:
obtain ⟨re, im, H1, Hre, Him⟩ := Int.exists_gcd_one hgcd
theorem exists_coprime_of_gcd_pos {a : ℤ√d} (hgcd : 0 < Int.gcd a.re a.im) :
    ∃ b : ℤ√d, a = ((Int.gcd a.re a.im : ℤ) : ℤ√d) * b ∧ IsCoprime b.re b.im := by
  obtain ⟨re, im, H1, Hre, Him⟩ := Int.exists_gcd_one hgcd
  

Proof state:
case intro.intro.intro.intro
d : ℤ
a : ℤ√d
hgcd : 0 < Int.gcd a.re a.im
re im : ℤ
H1 : Int.gcd re im = 1
Hre : a.re = re * ↑(Int.gcd a.re a.im)
Him : a.im = im * ↑(Int.gcd a.re a.im)
⊢ ∃ b, a = ↑↑(Int.gcd a.re a.im) * b ∧ IsCoprime b.re b.im

Next tactic:
rw [mul_comm] at Hre Him
theorem exists_coprime_of_gcd_pos {a : ℤ√d} (hgcd : 0 < Int.gcd a.re a.im) :
    ∃ b : ℤ√d, a = ((Int.gcd a.re a.im : ℤ) : ℤ√d) * b ∧ IsCoprime b.re b.im := by
  obtain ⟨re, im, H1, Hre, Him⟩ := Int.exists_gcd_one hgcd
  rw [mul_comm] at Hre Him
  

Proof state:
case intro.intro.intro.intro
d : ℤ
a : ℤ√d
hgcd : 0 < Int.gcd a.re a.im
re im : ℤ
H1 : Int.gcd re im = 1
Hre : a.re = ↑(Int.gcd a.re a.im) * re
Him : a.im = ↑(Int.gcd a.re a.im) * im
⊢ ∃ b, a = ↑↑(Int.gcd a.re a.im) * b ∧ IsCoprime b.re b.im

Next tactic:
refine' ⟨⟨re, im⟩, _, _⟩
theorem exists_coprime_of_gcd_pos {a : ℤ√d} (hgcd : 0 < Int.gcd a.re a.im) :
    ∃ b : ℤ√d, a = ((Int.gcd a.re a.im : ℤ) : ℤ√d) * b ∧ IsCoprime b.re b.im := by
  obtain ⟨re, im, H1, Hre, Him⟩ := Int.exists_gcd_one hgcd
  rw [mul_comm] at Hre Him
  refine' ⟨⟨re, im⟩, _, _⟩
  · 

Proof state:
case intro.intro.intro.intro.refine'_1
d : ℤ
a : ℤ√d
hgcd : 0 < Int.gcd a.re a.im
re im : ℤ
H1 : Int.gcd re im = 1
Hre : a.re = ↑(Int.gcd a.re a.im) * re
Him : a.im = ↑(Int.gcd a.re a.im) * im
⊢ a = ↑↑(Int.gcd a.re a.im) * { re := re, im := im }

Next tactic:
rw [smul_val, ext, ← Hre, ← Him]
theorem exists_coprime_of_gcd_pos {a : ℤ√d} (hgcd : 0 < Int.gcd a.re a.im) :
    ∃ b : ℤ√d, a = ((Int.gcd a.re a.im : ℤ) : ℤ√d) * b ∧ IsCoprime b.re b.im := by
  obtain ⟨re, im, H1, Hre, Him⟩ := Int.exists_gcd_one hgcd
  rw [mul_comm] at Hre Him
  refine' ⟨⟨re, im⟩, _, _⟩
  · rw [smul_val, ext, ← Hre, ← Him]
    

Proof state:
case intro.intro.intro.intro.refine'_1
d : ℤ
a : ℤ√d
hgcd : 0 < Int.gcd a.re a.im
re im : ℤ
H1 : Int.gcd re im = 1
Hre : a.re = ↑(Int.gcd a.re a.im) * re
Him : a.im = ↑(Int.gcd a.re a.im) * im
⊢ a.re = { re := a.re, im := a.im }.re ∧ a.im = { re := a.re, im := a.im }.im

Next tactic:
constructor
theorem exists_coprime_of_gcd_pos {a : ℤ√d} (hgcd : 0 < Int.gcd a.re a.im) :
    ∃ b : ℤ√d, a = ((Int.gcd a.re a.im : ℤ) : ℤ√d) * b ∧ IsCoprime b.re b.im := by
  obtain ⟨re, im, H1, Hre, Him⟩ := Int.exists_gcd_one hgcd
  rw [mul_comm] at Hre Him
  refine' ⟨⟨re, im⟩, _, _⟩
  · rw [smul_val, ext, ← Hre, ← Him]
    constructor <;> 

Proof state:
case intro.intro.intro.intro.refine'_1.left
d : ℤ
a : ℤ√d
hgcd : 0 < Int.gcd a.re a.im
re im : ℤ
H1 : Int.gcd re im = 1
Hre : a.re = ↑(Int.gcd a.re a.im) * re
Him : a.im = ↑(Int.gcd a.re a.im) * im
⊢ a.re = { re := a.re, im := a.im }.re

Next tactic:
rfl
theorem exists_coprime_of_gcd_pos {a : ℤ√d} (hgcd : 0 < Int.gcd a.re a.im) :
    ∃ b : ℤ√d, a = ((Int.gcd a.re a.im : ℤ) : ℤ√d) * b ∧ IsCoprime b.re b.im := by
  obtain ⟨re, im, H1, Hre, Him⟩ := Int.exists_gcd_one hgcd
  rw [mul_comm] at Hre Him
  refine' ⟨⟨re, im⟩, _, _⟩
  · rw [smul_val, ext, ← Hre, ← Him]
    constructor <;> 

Proof state:
case intro.intro.intro.intro.refine'_1.right
d : ℤ
a : ℤ√d
hgcd : 0 < Int.gcd a.re a.im
re im : ℤ
H1 : Int.gcd re im = 1
Hre : a.re = ↑(Int.gcd a.re a.im) * re
Him : a.im = ↑(Int.gcd a.re a.im) * im
⊢ a.im = { re := a.re, im := a.im }.im

Next tactic:
rfl
theorem exists_coprime_of_gcd_pos {a : ℤ√d} (hgcd : 0 < Int.gcd a.re a.im) :
    ∃ b : ℤ√d, a = ((Int.gcd a.re a.im : ℤ) : ℤ√d) * b ∧ IsCoprime b.re b.im := by
  obtain ⟨re, im, H1, Hre, Him⟩ := Int.exists_gcd_one hgcd
  rw [mul_comm] at Hre Him
  refine' ⟨⟨re, im⟩, _, _⟩
  · rw [smul_val, ext, ← Hre, ← Him]
    constructor <;> rfl
  · 

Proof state:
case intro.intro.intro.intro.refine'_2
d : ℤ
a : ℤ√d
hgcd : 0 < Int.gcd a.re a.im
re im : ℤ
H1 : Int.gcd re im = 1
Hre : a.re = ↑(Int.gcd a.re a.im) * re
Him : a.im = ↑(Int.gcd a.re a.im) * im
⊢ IsCoprime { re := re, im := im }.re { re := re, im := im }.im

Next tactic:
rw [← Int.gcd_eq_one_iff_coprime, H1]
theorem sqLe_add_mixed {c d x y z w : ℕ} (xy : SqLe x c y d) (zw : SqLe z c w d) :
    c * (x * z) ≤ d * (y * w) :=
  Nat.mul_self_le_mul_self_iff.2 <| by
    

Proof state:
d✝ : ℤ
c d x y z w : ℕ
xy : SqLe x c y d
zw : SqLe z c w d
⊢ c * (x * z) * (c * (x * z)) ≤ d * (y * w) * (d * (y * w))

Next tactic:
simpa [mul_comm, mul_left_comm] using mul_le_mul xy zw (Nat.zero_le _) (Nat.zero_le _)
theorem sqLe_add {c d x y z w : ℕ} (xy : SqLe x c y d) (zw : SqLe z c w d) :
    SqLe (x + z) c (y + w) d := by
  

Proof state:
d✝ : ℤ
c d x y z w : ℕ
xy : SqLe x c y d
zw : SqLe z c w d
⊢ SqLe (x + z) c (y + w) d

Next tactic:
have xz := sqLe_add_mixed xy zw
theorem sqLe_add {c d x y z w : ℕ} (xy : SqLe x c y d) (zw : SqLe z c w d) :
    SqLe (x + z) c (y + w) d := by
  have xz := sqLe_add_mixed xy zw
  

Proof state:
d✝ : ℤ
c d x y z w : ℕ
xy : SqLe x c y d
zw : SqLe z c w d
xz : c * (x * z) ≤ d * (y * w)
⊢ SqLe (x + z) c (y + w) d

Next tactic:
simp? [SqLe, mul_assoc] at xy zw says simp only [SqLe, mul_assoc] at xy zw
theorem sqLe_add {c d x y z w : ℕ} (xy : SqLe x c y d) (zw : SqLe z c w d) :
    SqLe (x + z) c (y + w) d := by
  have xz := sqLe_add_mixed xy zw
  simp? [SqLe, mul_assoc] at xy zw says 

Proof state:
d✝ : ℤ
c d x y z w : ℕ
xy : SqLe x c y d
zw : SqLe z c w d
xz : c * (x * z) ≤ d * (y * w)
⊢ SqLe (x + z) c (y + w) d

Next tactic:
simp only [SqLe, mul_assoc] at xy zw
theorem sqLe_add {c d x y z w : ℕ} (xy : SqLe x c y d) (zw : SqLe z c w d) :
    SqLe (x + z) c (y + w) d := by
  have xz := sqLe_add_mixed xy zw
  simp? [SqLe, mul_assoc] at xy zw says simp only [SqLe, mul_assoc] at xy zw
  

Proof state:
d✝ : ℤ
c d x y z w : ℕ
xz : c * (x * z) ≤ d * (y * w)
xy : c * (x * x) ≤ d * (y * y)
zw : c * (z * z) ≤ d * (w * w)
⊢ SqLe (x + z) c (y + w) d

Next tactic:
simp [SqLe, mul_add, mul_comm, mul_left_comm, add_le_add, *]
theorem sqLe_cancel {c d x y z w : ℕ} (zw : SqLe y d x c) (h : SqLe (x + z) c (y + w) d) :
    SqLe z c w d := by
  

Proof state:
d✝ : ℤ
c d x y z w : ℕ
zw : SqLe y d x c
h : SqLe (x + z) c (y + w) d
⊢ SqLe z c w d

Next tactic:
apply le_of_not_gt
theorem sqLe_cancel {c d x y z w : ℕ} (zw : SqLe y d x c) (h : SqLe (x + z) c (y + w) d) :
    SqLe z c w d := by
  apply le_of_not_gt
  

Proof state:
case a
d✝ : ℤ
c d x y z w : ℕ
zw : SqLe y d x c
h : SqLe (x + z) c (y + w) d
⊢ ¬c * z * z > d * w * w

Next tactic:
intro l
theorem sqLe_cancel {c d x y z w : ℕ} (zw : SqLe y d x c) (h : SqLe (x + z) c (y + w) d) :
    SqLe z c w d := by
  apply le_of_not_gt
  intro l
  

Proof state:
case a
d✝ : ℤ
c d x y z w : ℕ
zw : SqLe y d x c
h : SqLe (x + z) c (y + w) d
l : c * z * z > d * w * w
⊢ False

Next tactic:
refine' not_le_of_gt _ h
theorem sqLe_cancel {c d x y z w : ℕ} (zw : SqLe y d x c) (h : SqLe (x + z) c (y + w) d) :
    SqLe z c w d := by
  apply le_of_not_gt
  intro l
  refine' not_le_of_gt _ h
  

Proof state:
case a
d✝ : ℤ
c d x y z w : ℕ
zw : SqLe y d x c
h : SqLe (x + z) c (y + w) d
l : c * z * z > d * w * w
⊢ c * (x + z) * (x + z) > d * (y + w) * (y + w)

Next tactic:
simp only [SqLe, mul_add, mul_comm, mul_left_comm, add_assoc, gt_iff_lt]
theorem sqLe_cancel {c d x y z w : ℕ} (zw : SqLe y d x c) (h : SqLe (x + z) c (y + w) d) :
    SqLe z c w d := by
  apply le_of_not_gt
  intro l
  refine' not_le_of_gt _ h
  simp only [SqLe, mul_add, mul_comm, mul_left_comm, add_assoc, gt_iff_lt]
  

Proof state:
case a
d✝ : ℤ
c d x y z w : ℕ
zw : SqLe y d x c
h : SqLe (x + z) c (y + w) d
l : c * z * z > d * w * w
⊢ d * (y * y) + (d * (y * w) + (d * (y * w) + d * (w * w))) < c * (x * x) + (c * (x * z) + (c * (x * z) + c * (z * z)))

Next tactic:
have hm := sqLe_add_mixed zw (le_of_lt l)
theorem sqLe_cancel {c d x y z w : ℕ} (zw : SqLe y d x c) (h : SqLe (x + z) c (y + w) d) :
    SqLe z c w d := by
  apply le_of_not_gt
  intro l
  refine' not_le_of_gt _ h
  simp only [SqLe, mul_add, mul_comm, mul_left_comm, add_assoc, gt_iff_lt]
  have hm := sqLe_add_mixed zw (le_of_lt l)
  

Proof state:
case a
d✝ : ℤ
c d x y z w : ℕ
zw : SqLe y d x c
h : SqLe (x + z) c (y + w) d
l : c * z * z > d * w * w
hm : d * (y * w) ≤ c * (x * z)
⊢ d * (y * y) + (d * (y * w) + (d * (y * w) + d * (w * w))) < c * (x * x) + (c * (x * z) + (c * (x * z) + c * (z * z)))

Next tactic:
simp only [SqLe, mul_assoc, gt_iff_lt] at l zw
theorem sqLe_cancel {c d x y z w : ℕ} (zw : SqLe y d x c) (h : SqLe (x + z) c (y + w) d) :
    SqLe z c w d := by
  apply le_of_not_gt
  intro l
  refine' not_le_of_gt _ h
  simp only [SqLe, mul_add, mul_comm, mul_left_comm, add_assoc, gt_iff_lt]
  have hm := sqLe_add_mixed zw (le_of_lt l)
  simp only [SqLe, mul_assoc, gt_iff_lt] at l zw
  

Proof state:
case a
d✝ : ℤ
c d x y z w : ℕ
h : SqLe (x + z) c (y + w) d
hm : d * (y * w) ≤ c * (x * z)
l : d * (w * w) < c * (z * z)
zw : d * (y * y) ≤ c * (x * x)
⊢ d * (y * y) + (d * (y * w) + (d * (y * w) + d * (w * w))) < c * (x * x) + (c * (x * z) + (c * (x * z) + c * (z * z)))

Next tactic:
exact
    lt_of_le_of_lt (add_le_add_right zw _)
      (add_lt_add_left (add_lt_add_of_le_of_lt hm (add_lt_add_of_le_of_lt hm l)) _)
theorem sqLe_smul {c d x y : ℕ} (n : ℕ) (xy : SqLe x c y d) : SqLe (n * x) c (n * y) d := by
  

Proof state:
d✝ : ℤ
c d x y n : ℕ
xy : SqLe x c y d
⊢ SqLe (n * x) c (n * y) d

Next tactic:
simpa [SqLe, mul_left_comm, mul_assoc] using Nat.mul_le_mul_left (n * n) xy
theorem sqLe_mul {d x y z w : ℕ} :
    (SqLe x 1 y d → SqLe z 1 w d → SqLe (x * w + y * z) d (x * z + d * y * w) 1) ∧
      (SqLe x 1 y d → SqLe w d z 1 → SqLe (x * z + d * y * w) 1 (x * w + y * z) d) ∧
        (SqLe y d x 1 → SqLe z 1 w d → SqLe (x * z + d * y * w) 1 (x * w + y * z) d) ∧
          (SqLe y d x 1 → SqLe w d z 1 → SqLe (x * w + y * z) d (x * z + d * y * w) 1) := by
  

Proof state:
d✝ : ℤ
d x y z w : ℕ
⊢ (SqLe x 1 y d → SqLe z 1 w d → SqLe (x * w + y * z) d (x * z + d * y * w) 1) ∧
    (SqLe x 1 y d → SqLe w d z 1 → SqLe (x * z + d * y * w) 1 (x * w + y * z) d) ∧
      (SqLe y d x 1 → SqLe z 1 w d → SqLe (x * z + d * y * w) 1 (x * w + y * z) d) ∧
        (SqLe y d x 1 → SqLe w d z 1 → SqLe (x * w + y * z) d (x * z + d * y * w) 1)

Next tactic:
refine' ⟨_, _, _, _⟩
theorem sqLe_mul {d x y z w : ℕ} :
    (SqLe x 1 y d → SqLe z 1 w d → SqLe (x * w + y * z) d (x * z + d * y * w) 1) ∧
      (SqLe x 1 y d → SqLe w d z 1 → SqLe (x * z + d * y * w) 1 (x * w + y * z) d) ∧
        (SqLe y d x 1 → SqLe z 1 w d → SqLe (x * z + d * y * w) 1 (x * w + y * z) d) ∧
          (SqLe y d x 1 → SqLe w d z 1 → SqLe (x * w + y * z) d (x * z + d * y * w) 1) := by
  refine' ⟨_, _, _, _⟩ <;>
    · 

Proof state:
case refine'_1
d✝ : ℤ
d x y z w : ℕ
⊢ SqLe x 1 y d → SqLe z 1 w d → SqLe (x * w + y * z) d (x * z + d * y * w) 1

Next tactic:
intro xy zw
theorem sqLe_mul {d x y z w : ℕ} :
    (SqLe x 1 y d → SqLe z 1 w d → SqLe (x * w + y * z) d (x * z + d * y * w) 1) ∧
      (SqLe x 1 y d → SqLe w d z 1 → SqLe (x * z + d * y * w) 1 (x * w + y * z) d) ∧
        (SqLe y d x 1 → SqLe z 1 w d → SqLe (x * z + d * y * w) 1 (x * w + y * z) d) ∧
          (SqLe y d x 1 → SqLe w d z 1 → SqLe (x * w + y * z) d (x * z + d * y * w) 1) := by
  refine' ⟨_, _, _, _⟩ <;>
    · intro xy zw
      

Proof state:
case refine'_1
d✝ : ℤ
d x y z w : ℕ
xy : SqLe x 1 y d
zw : SqLe z 1 w d
⊢ SqLe (x * w + y * z) d (x * z + d * y * w) 1

Next tactic:
have :=
        Int.mul_nonneg (sub_nonneg_of_le (Int.ofNat_le_ofNat_of_le xy))
          (sub_nonneg_of_le (Int.ofNat_le_ofNat_of_le zw))
theorem sqLe_mul {d x y z w : ℕ} :
    (SqLe x 1 y d → SqLe z 1 w d → SqLe (x * w + y * z) d (x * z + d * y * w) 1) ∧
      (SqLe x 1 y d → SqLe w d z 1 → SqLe (x * z + d * y * w) 1 (x * w + y * z) d) ∧
        (SqLe y d x 1 → SqLe z 1 w d → SqLe (x * z + d * y * w) 1 (x * w + y * z) d) ∧
          (SqLe y d x 1 → SqLe w d z 1 → SqLe (x * w + y * z) d (x * z + d * y * w) 1) := by
  refine' ⟨_, _, _, _⟩ <;>
    · intro xy zw
      have :=
        Int.mul_nonneg (sub_nonneg_of_le (Int.ofNat_le_ofNat_of_le xy))
          (sub_nonneg_of_le (Int.ofNat_le_ofNat_of_le zw))
      

Proof state:
case refine'_1
d✝ : ℤ
d x y z w : ℕ
xy : SqLe x 1 y d
zw : SqLe z 1 w d
this : 0 ≤ (↑(d * y * y) - ↑(1 * x * x)) * (↑(d * w * w) - ↑(1 * z * z))
⊢ SqLe (x * w + y * z) d (x * z + d * y * w) 1

Next tactic:
refine' Int.le_of_ofNat_le_ofNat (le_of_sub_nonneg _)
theorem sqLe_mul {d x y z w : ℕ} :
    (SqLe x 1 y d → SqLe z 1 w d → SqLe (x * w + y * z) d (x * z + d * y * w) 1) ∧
      (SqLe x 1 y d → SqLe w d z 1 → SqLe (x * z + d * y * w) 1 (x * w + y * z) d) ∧
        (SqLe y d x 1 → SqLe z 1 w d → SqLe (x * z + d * y * w) 1 (x * w + y * z) d) ∧
          (SqLe y d x 1 → SqLe w d z 1 → SqLe (x * w + y * z) d (x * z + d * y * w) 1) := by
  refine' ⟨_, _, _, _⟩ <;>
    · intro xy zw
      have :=
        Int.mul_nonneg (sub_nonneg_of_le (Int.ofNat_le_ofNat_of_le xy))
          (sub_nonneg_of_le (Int.ofNat_le_ofNat_of_le zw))
      refine' Int.le_of_ofNat_le_ofNat (le_of_sub_nonneg _)
      

Proof state:
case refine'_1
d✝ : ℤ
d x y z w : ℕ
xy : SqLe x 1 y d
zw : SqLe z 1 w d
this : 0 ≤ (↑(d * y * y) - ↑(1 * x * x)) * (↑(d * w * w) - ↑(1 * z * z))
⊢ 0 ≤ ↑(1 * (x * z + d * y * w) * (x * z + d * y * w)) - ↑(d * (x * w + y * z) * (x * w + y * z))

Next tactic:
convert this using 1
theorem sqLe_mul {d x y z w : ℕ} :
    (SqLe x 1 y d → SqLe z 1 w d → SqLe (x * w + y * z) d (x * z + d * y * w) 1) ∧
      (SqLe x 1 y d → SqLe w d z 1 → SqLe (x * z + d * y * w) 1 (x * w + y * z) d) ∧
        (SqLe y d x 1 → SqLe z 1 w d → SqLe (x * z + d * y * w) 1 (x * w + y * z) d) ∧
          (SqLe y d x 1 → SqLe w d z 1 → SqLe (x * w + y * z) d (x * z + d * y * w) 1) := by
  refine' ⟨_, _, _, _⟩ <;>
    · intro xy zw
      have :=
        Int.mul_nonneg (sub_nonneg_of_le (Int.ofNat_le_ofNat_of_le xy))
          (sub_nonneg_of_le (Int.ofNat_le_ofNat_of_le zw))
      refine' Int.le_of_ofNat_le_ofNat (le_of_sub_nonneg _)
      convert this using 1
      

Proof state:
case h.e'_4
d✝ : ℤ
d x y z w : ℕ
xy : SqLe x 1 y d
zw : SqLe z 1 w d
this : 0 ≤ (↑(d * y * y) - ↑(1 * x * x)) * (↑(d * w * w) - ↑(1 * z * z))
⊢ ↑(1 * (x * z + d * y * w) * (x * z + d * y * w)) - ↑(d * (x * w + y * z) * (x * w + y * z)) =
    (↑(d * y * y) - ↑(1 * x * x)) * (↑(d * w * w) - ↑(1 * z * z))

Next tactic:
simp only [one_mul, Int.ofNat_add, Int.ofNat_mul]
theorem sqLe_mul {d x y z w : ℕ} :
    (SqLe x 1 y d → SqLe z 1 w d → SqLe (x * w + y * z) d (x * z + d * y * w) 1) ∧
      (SqLe x 1 y d → SqLe w d z 1 → SqLe (x * z + d * y * w) 1 (x * w + y * z) d) ∧
        (SqLe y d x 1 → SqLe z 1 w d → SqLe (x * z + d * y * w) 1 (x * w + y * z) d) ∧
          (SqLe y d x 1 → SqLe w d z 1 → SqLe (x * w + y * z) d (x * z + d * y * w) 1) := by
  refine' ⟨_, _, _, _⟩ <;>
    · intro xy zw
      have :=
        Int.mul_nonneg (sub_nonneg_of_le (Int.ofNat_le_ofNat_of_le xy))
          (sub_nonneg_of_le (Int.ofNat_le_ofNat_of_le zw))
      refine' Int.le_of_ofNat_le_ofNat (le_of_sub_nonneg _)
      convert this using 1
      simp only [one_mul, Int.ofNat_add, Int.ofNat_mul]
      

Proof state:
case h.e'_4
d✝ : ℤ
d x y z w : ℕ
xy : SqLe x 1 y d
zw : SqLe z 1 w d
this : 0 ≤ (↑(d * y * y) - ↑(1 * x * x)) * (↑(d * w * w) - ↑(1 * z * z))
⊢ (↑x * ↑z + ↑d * ↑y * ↑w) * (↑x * ↑z + ↑d * ↑y * ↑w) - ↑d * (↑x * ↑w + ↑y * ↑z) * (↑x * ↑w + ↑y * ↑z) =
    (↑d * ↑y * ↑y - ↑x * ↑x) * (↑d * ↑w * ↑w - ↑z * ↑z)

Next tactic:
ring
theorem sqLe_mul {d x y z w : ℕ} :
    (SqLe x 1 y d → SqLe z 1 w d → SqLe (x * w + y * z) d (x * z + d * y * w) 1) ∧
      (SqLe x 1 y d → SqLe w d z 1 → SqLe (x * z + d * y * w) 1 (x * w + y * z) d) ∧
        (SqLe y d x 1 → SqLe z 1 w d → SqLe (x * z + d * y * w) 1 (x * w + y * z) d) ∧
          (SqLe y d x 1 → SqLe w d z 1 → SqLe (x * w + y * z) d (x * z + d * y * w) 1) := by
  refine' ⟨_, _, _, _⟩ <;>
    · 

Proof state:
case refine'_2
d✝ : ℤ
d x y z w : ℕ
⊢ SqLe x 1 y d → SqLe w d z 1 → SqLe (x * z + d * y * w) 1 (x * w + y * z) d

Next tactic:
intro xy zw
theorem sqLe_mul {d x y z w : ℕ} :
    (SqLe x 1 y d → SqLe z 1 w d → SqLe (x * w + y * z) d (x * z + d * y * w) 1) ∧
      (SqLe x 1 y d → SqLe w d z 1 → SqLe (x * z + d * y * w) 1 (x * w + y * z) d) ∧
        (SqLe y d x 1 → SqLe z 1 w d → SqLe (x * z + d * y * w) 1 (x * w + y * z) d) ∧
          (SqLe y d x 1 → SqLe w d z 1 → SqLe (x * w + y * z) d (x * z + d * y * w) 1) := by
  refine' ⟨_, _, _, _⟩ <;>
    · intro xy zw
      

Proof state:
case refine'_2
d✝ : ℤ
d x y z w : ℕ
xy : SqLe x 1 y d
zw : SqLe w d z 1
⊢ SqLe (x * z + d * y * w) 1 (x * w + y * z) d

Next tactic:
have :=
        Int.mul_nonneg (sub_nonneg_of_le (Int.ofNat_le_ofNat_of_le xy))
          (sub_nonneg_of_le (Int.ofNat_le_ofNat_of_le zw))
theorem sqLe_mul {d x y z w : ℕ} :
    (SqLe x 1 y d → SqLe z 1 w d → SqLe (x * w + y * z) d (x * z + d * y * w) 1) ∧
      (SqLe x 1 y d → SqLe w d z 1 → SqLe (x * z + d * y * w) 1 (x * w + y * z) d) ∧
        (SqLe y d x 1 → SqLe z 1 w d → SqLe (x * z + d * y * w) 1 (x * w + y * z) d) ∧
          (SqLe y d x 1 → SqLe w d z 1 → SqLe (x * w + y * z) d (x * z + d * y * w) 1) := by
  refine' ⟨_, _, _, _⟩ <;>
    · intro xy zw
      have :=
        Int.mul_nonneg (sub_nonneg_of_le (Int.ofNat_le_ofNat_of_le xy))
          (sub_nonneg_of_le (Int.ofNat_le_ofNat_of_le zw))
      

Proof state:
case refine'_2
d✝ : ℤ
d x y z w : ℕ
xy : SqLe x 1 y d
zw : SqLe w d z 1
this : 0 ≤ (↑(d * y * y) - ↑(1 * x * x)) * (↑(1 * z * z) - ↑(d * w * w))
⊢ SqLe (x * z + d * y * w) 1 (x * w + y * z) d

Next tactic:
refine' Int.le_of_ofNat_le_ofNat (le_of_sub_nonneg _)
theorem sqLe_mul {d x y z w : ℕ} :
    (SqLe x 1 y d → SqLe z 1 w d → SqLe (x * w + y * z) d (x * z + d * y * w) 1) ∧
      (SqLe x 1 y d → SqLe w d z 1 → SqLe (x * z + d * y * w) 1 (x * w + y * z) d) ∧
        (SqLe y d x 1 → SqLe z 1 w d → SqLe (x * z + d * y * w) 1 (x * w + y * z) d) ∧
          (SqLe y d x 1 → SqLe w d z 1 → SqLe (x * w + y * z) d (x * z + d * y * w) 1) := by
  refine' ⟨_, _, _, _⟩ <;>
    · intro xy zw
      have :=
        Int.mul_nonneg (sub_nonneg_of_le (Int.ofNat_le_ofNat_of_le xy))
          (sub_nonneg_of_le (Int.ofNat_le_ofNat_of_le zw))
      refine' Int.le_of_ofNat_le_ofNat (le_of_sub_nonneg _)
      

Proof state:
case refine'_2
d✝ : ℤ
d x y z w : ℕ
xy : SqLe x 1 y d
zw : SqLe w d z 1
this : 0 ≤ (↑(d * y * y) - ↑(1 * x * x)) * (↑(1 * z * z) - ↑(d * w * w))
⊢ 0 ≤ ↑(d * (x * w + y * z) * (x * w + y * z)) - ↑(1 * (x * z + d * y * w) * (x * z + d * y * w))

Next tactic:
convert this using 1
theorem sqLe_mul {d x y z w : ℕ} :
    (SqLe x 1 y d → SqLe z 1 w d → SqLe (x * w + y * z) d (x * z + d * y * w) 1) ∧
      (SqLe x 1 y d → SqLe w d z 1 → SqLe (x * z + d * y * w) 1 (x * w + y * z) d) ∧
        (SqLe y d x 1 → SqLe z 1 w d → SqLe (x * z + d * y * w) 1 (x * w + y * z) d) ∧
          (SqLe y d x 1 → SqLe w d z 1 → SqLe (x * w + y * z) d (x * z + d * y * w) 1) := by
  refine' ⟨_, _, _, _⟩ <;>
    · intro xy zw
      have :=
        Int.mul_nonneg (sub_nonneg_of_le (Int.ofNat_le_ofNat_of_le xy))
          (sub_nonneg_of_le (Int.ofNat_le_ofNat_of_le zw))
      refine' Int.le_of_ofNat_le_ofNat (le_of_sub_nonneg _)
      convert this using 1
      

Proof state:
case h.e'_4
d✝ : ℤ
d x y z w : ℕ
xy : SqLe x 1 y d
zw : SqLe w d z 1
this : 0 ≤ (↑(d * y * y) - ↑(1 * x * x)) * (↑(1 * z * z) - ↑(d * w * w))
⊢ ↑(d * (x * w + y * z) * (x * w + y * z)) - ↑(1 * (x * z + d * y * w) * (x * z + d * y * w)) =
    (↑(d * y * y) - ↑(1 * x * x)) * (↑(1 * z * z) - ↑(d * w * w))

Next tactic:
simp only [one_mul, Int.ofNat_add, Int.ofNat_mul]
theorem sqLe_mul {d x y z w : ℕ} :
    (SqLe x 1 y d → SqLe z 1 w d → SqLe (x * w + y * z) d (x * z + d * y * w) 1) ∧
      (SqLe x 1 y d → SqLe w d z 1 → SqLe (x * z + d * y * w) 1 (x * w + y * z) d) ∧
        (SqLe y d x 1 → SqLe z 1 w d → SqLe (x * z + d * y * w) 1 (x * w + y * z) d) ∧
          (SqLe y d x 1 → SqLe w d z 1 → SqLe (x * w + y * z) d (x * z + d * y * w) 1) := by
  refine' ⟨_, _, _, _⟩ <;>
    · intro xy zw
      have :=
        Int.mul_nonneg (sub_nonneg_of_le (Int.ofNat_le_ofNat_of_le xy))
          (sub_nonneg_of_le (Int.ofNat_le_ofNat_of_le zw))
      refine' Int.le_of_ofNat_le_ofNat (le_of_sub_nonneg _)
      convert this using 1
      simp only [one_mul, Int.ofNat_add, Int.ofNat_mul]
      

Proof state:
case h.e'_4
d✝ : ℤ
d x y z w : ℕ
xy : SqLe x 1 y d
zw : SqLe w d z 1
this : 0 ≤ (↑(d * y * y) - ↑(1 * x * x)) * (↑(1 * z * z) - ↑(d * w * w))
⊢ ↑d * (↑x * ↑w + ↑y * ↑z) * (↑x * ↑w + ↑y * ↑z) - (↑x * ↑z + ↑d * ↑y * ↑w) * (↑x * ↑z + ↑d * ↑y * ↑w) =
    (↑d * ↑y * ↑y - ↑x * ↑x) * (↑z * ↑z - ↑d * ↑w * ↑w)

Next tactic:
ring
theorem sqLe_mul {d x y z w : ℕ} :
    (SqLe x 1 y d → SqLe z 1 w d → SqLe (x * w + y * z) d (x * z + d * y * w) 1) ∧
      (SqLe x 1 y d → SqLe w d z 1 → SqLe (x * z + d * y * w) 1 (x * w + y * z) d) ∧
        (SqLe y d x 1 → SqLe z 1 w d → SqLe (x * z + d * y * w) 1 (x * w + y * z) d) ∧
          (SqLe y d x 1 → SqLe w d z 1 → SqLe (x * w + y * z) d (x * z + d * y * w) 1) := by
  refine' ⟨_, _, _, _⟩ <;>
    · 

Proof state:
case refine'_3
d✝ : ℤ
d x y z w : ℕ
⊢ SqLe y d x 1 → SqLe z 1 w d → SqLe (x * z + d * y * w) 1 (x * w + y * z) d

Next tactic:
intro xy zw
theorem sqLe_mul {d x y z w : ℕ} :
    (SqLe x 1 y d → SqLe z 1 w d → SqLe (x * w + y * z) d (x * z + d * y * w) 1) ∧
      (SqLe x 1 y d → SqLe w d z 1 → SqLe (x * z + d * y * w) 1 (x * w + y * z) d) ∧
        (SqLe y d x 1 → SqLe z 1 w d → SqLe (x * z + d * y * w) 1 (x * w + y * z) d) ∧
          (SqLe y d x 1 → SqLe w d z 1 → SqLe (x * w + y * z) d (x * z + d * y * w) 1) := by
  refine' ⟨_, _, _, _⟩ <;>
    · intro xy zw
      

Proof state:
case refine'_3
d✝ : ℤ
d x y z w : ℕ
xy : SqLe y d x 1
zw : SqLe z 1 w d
⊢ SqLe (x * z + d * y * w) 1 (x * w + y * z) d

Next tactic:
have :=
        Int.mul_nonneg (sub_nonneg_of_le (Int.ofNat_le_ofNat_of_le xy))
          (sub_nonneg_of_le (Int.ofNat_le_ofNat_of_le zw))
theorem sqLe_mul {d x y z w : ℕ} :
    (SqLe x 1 y d → SqLe z 1 w d → SqLe (x * w + y * z) d (x * z + d * y * w) 1) ∧
      (SqLe x 1 y d → SqLe w d z 1 → SqLe (x * z + d * y * w) 1 (x * w + y * z) d) ∧
        (SqLe y d x 1 → SqLe z 1 w d → SqLe (x * z + d * y * w) 1 (x * w + y * z) d) ∧
          (SqLe y d x 1 → SqLe w d z 1 → SqLe (x * w + y * z) d (x * z + d * y * w) 1) := by
  refine' ⟨_, _, _, _⟩ <;>
    · intro xy zw
      have :=
        Int.mul_nonneg (sub_nonneg_of_le (Int.ofNat_le_ofNat_of_le xy))
          (sub_nonneg_of_le (Int.ofNat_le_ofNat_of_le zw))
      

Proof state:
case refine'_3
d✝ : ℤ
d x y z w : ℕ
xy : SqLe y d x 1
zw : SqLe z 1 w d
this : 0 ≤ (↑(1 * x * x) - ↑(d * y * y)) * (↑(d * w * w) - ↑(1 * z * z))
⊢ SqLe (x * z + d * y * w) 1 (x * w + y * z) d

Next tactic:
refine' Int.le_of_ofNat_le_ofNat (le_of_sub_nonneg _)
theorem sqLe_mul {d x y z w : ℕ} :
    (SqLe x 1 y d → SqLe z 1 w d → SqLe (x * w + y * z) d (x * z + d * y * w) 1) ∧
      (SqLe x 1 y d → SqLe w d z 1 → SqLe (x * z + d * y * w) 1 (x * w + y * z) d) ∧
        (SqLe y d x 1 → SqLe z 1 w d → SqLe (x * z + d * y * w) 1 (x * w + y * z) d) ∧
          (SqLe y d x 1 → SqLe w d z 1 → SqLe (x * w + y * z) d (x * z + d * y * w) 1) := by
  refine' ⟨_, _, _, _⟩ <;>
    · intro xy zw
      have :=
        Int.mul_nonneg (sub_nonneg_of_le (Int.ofNat_le_ofNat_of_le xy))
          (sub_nonneg_of_le (Int.ofNat_le_ofNat_of_le zw))
      refine' Int.le_of_ofNat_le_ofNat (le_of_sub_nonneg _)
      

Proof state:
case refine'_3
d✝ : ℤ
d x y z w : ℕ
xy : SqLe y d x 1
zw : SqLe z 1 w d
this : 0 ≤ (↑(1 * x * x) - ↑(d * y * y)) * (↑(d * w * w) - ↑(1 * z * z))
⊢ 0 ≤ ↑(d * (x * w + y * z) * (x * w + y * z)) - ↑(1 * (x * z + d * y * w) * (x * z + d * y * w))

Next tactic:
convert this using 1