⊦ abs(abs(i)) = abs(i)
abs(i0) < abs(gcd(i, i0)), gcd(i, i0) ≠ 0, abs(i0) ≠ 0, 0 ≤ gcd(i, i0), 0 = 0 ⊦ i = 0, i0 = 0
Used terms: i0