| j0 < j ⊦ i + j0 < i0, i0 < i + j |
j0 < j ⊦ i0 < i + j, i + j0 < i0, i + j ≤ i + j0
Used simplifier rules: le-add: ⊦ i + j ≤ i0 + j ↔ i ≤ i0;%lels-03: ⊦ i < j → (j ≤ i ↔ false);%add-a: ⊦ i + j + i0 = (i + j) + i0; from specification int-basic2%add-c: ⊦ i + j = j + i; from specification int-basic2 Used formulas: i + j ≤ i + j0