⊦ i < j ↔ ¬ j ≤ i
⊦ i * j = 1 ↔ abs(j) = 1 ∧ i = j, ¬ i ≤ 0 ∧ 1 < j, ¬ i ≤ 0 ∧ ¬ 0 ≤ j, i < 0 ∧ 0 < j
Used terms: 0, j