⊦ ¬ i < j → (i = j ↔ ¬ j < i)
gcd(i, j) < gcd(abs(i), abs(j)) ⊦ gcd(i, j) = gcd(abs(i), abs(j))
gcd(abs(i), abs(j)) < gcd(i, j) ⊦ gcd(i, j) < gcd(abs(i), abs(j))
Used terms: gcd(abs(i), abs(j)), gcd(i, j)