i < ~1, i < 0 ⊦ # int2bits(i) ≤ m ↔ ¬ i + 2 ^ (n→i(m) - 1) < 0
Used simplifier rules: ⊦ i < (* j) ∧ j < 0 → i < 0; (forward)% ⊦ ¬ i ≤ j ↔ j < i;