| 0 < j, gcd(i, j) = 1, 0 < j, j ≤ i0, 0 < i0, j | abs(i * i0 - 1), 0 ≤ i0, 0 < i, i0 |%| j < j, i0 |%| j < i0, 0 ≤ i0 |%| j ⊦ i = 0, j = 0, (i * i0 |%| j) |%| j = 1 |%| j |
gcd(i, j) = 1, 0 ≤ i0, 0 < i, i0 |%| j < j, i0 |%| j < i0, 0 ≤ i0 |%| j, 0 < j, j ≤ i0, 0 < i0, j | i * i0 - 1 ⊦ i = 0, j = 0, (i * i0 |%| j) |%| j = 1 |%| j
Used simplifier rules: div-abs-02: ⊦ i | abs(j) ↔ i | j; from specification int-gcd