| ⊦ abs(i + 1) ≤ abs(i) ↔ i < 0 |
⊦ i < 0, i < abs(i + 1)
Used simplifier rules: Abs-pos: ⊦ ¬ j < 0 → abs(j) = j;%le-def: ⊦ i ≤ j ↔ ¬ j < i;%abs-05: ⊦ i < 0 → abs(i + 1) = abs(i) - 1;%abs-08: ⊦ i < 0 → abs(i) = ~ i;%Minus-def: ⊦ ~ i = 0 - i;%sub-sub: ⊦ i - j - i0 = i - j + i0;%num-subadd: ⊦ (* i) - j + (* i0) = i - i0 - j;%sub-le: ⊦ i - j ≤ i0 ↔ i ≤ j + i0;%sub-zero: ⊦ i + (0 - i0) = i - i0;%sub-sub-03: ⊦ i - i = 0;%add-c: ⊦ i + j = j + i; from specification int-basic2%add-a: ⊦ i + j + i0 = (i + j) + i0; from specification int-basic2