| abs(i) = i0 * abs(j) + j0, j0 < abs(j), gcd(abs(i), abs(j)) < gcd(abs(j), j0), gcd(abs(j), j0) | abs(j), 0 ≤ j0, 0 ≤ i0 ⊦ gcd(abs(i), abs(j)) = gcd(abs(j), j0), i = 0, j = 0, gcd(abs(j), j0) | abs(i) |
⊦ gcd(i, j) | j
abs(i) = i0 * abs(j) + j0, gcd(abs(i), abs(j)) < gcd(abs(j), j0), j0 < abs(j), gcd(abs(j), j0) | abs(j), gcd(abs(j), j0) | j0, 0 ≤ i0, 0 ≤ j0 ⊦ gcd(abs(i), abs(j)) = gcd(abs(j), j0), i = 0, j = 0, gcd(abs(j), j0) | abs(i)
Used terms: abs(j), j0