| ⊦ j ≠ 0 → rational(~ i, ~ j).num = rational(i, j).num |
⊦ i ≠ 0 ∧ 0 < j → rational(i, j).num = i / gcd(i, j)
¬(~ i ≠ 0 ∧ 0 < ~ j) ⊦ j ≠ 0 → rational(~ i, ~ j).num = rational(i, j).num
~ i ≠ 0 ∧ 0 < ~ j ⊦ j ≠ 0 → ~ i / gcd(~ i, ~ j) = rational(i, j).num
Used terms: ~ j, ~ i