| gcd(abs(j), abs(i)) = abs(j) * i0 + abs(i) * j0, i < 0, abs(i) < abs(j), j < 0 ⊦ ∃ i0, j0. gcd(abs(i), abs(j)) = i * i0 + j * j0 |
Used simplifier rules: gcd-neg: ⊦ gcd(~ i, j) = gcd(i, j);%gcd-com: ⊦ gcd(i, j) = gcd(j, i);% ⊦ i < 0 → abs(i) = ~ i; (s)% ⊦ ~ i * j = ~(i * j); (s)%associativity: ⊦ i * j * j0 = (i * j) * j0; from specification int-mult%commutativity: ⊦ i * j = j * i; from specification int-mult% ⊦ ~ i + ~ j = ~(i + j); (s)%add-a: ⊦ i + j + i0 = (i + j) + i0; from specification int-basic2%add-c: ⊦ i + j = j + i; from specification int-basic2% ⊦ ~ i = j ↔ i + j = 0; (s) Used terms: ~ j0, ~ i0