0 ≤ i, 0 < j ⊦ rational(i, j) = rational(i / gcd(i, j), j / gcd(i, j))
Used simplifier rules: ⊦ i ≤ j ∧ 0 ≤ i → 0 ≤ j; (forward)% ⊦ i < j ∧ 0 ≤ i → 0 < j; (forward)