have : ¬ Even (3 : ℤ) := by decide
q s : ℤ
h3_ndvd_q : ¬3 ∣ q
hspos : s ≠ 0
hcoprime' : IsCoprime s q
hodd' : Even q ↔ ¬Even s
⊢ ¬Even (q ^ 2 + 3 * s ^ 2)
q s : ℤ
h3_ndvd_q : ¬3 ∣ q
hspos : s ≠ 0
hcoprime' : IsCoprime s q
hodd' : Even q ↔ ¬Even s
this : ¬Even 3
⊢ ¬Even (q ^ 2 + 3 * s ^ 2)