0 ≤ i ⊦ i + n→i(n) < n→i(m) ↔ i→n(i) + n < m
Used simplifier rules: forward-le-01: ⊦ i ≤ j ∧ 0 ≤ i → 0 ≤ j; (forward) from specification int-abs% ⊦ i < j ↔ ¬ j ≤ i; (ss)% ⊦ i ≥ j ↔ ¬ i < j; (s)