| i % 10 = 0 ∧ j ≠ 0 ∧ i ≠ 0, mkDecimal(i / 10, abs(j) - 1).int = 0, ∀ i0, j. i→n(i0) < i→n(i) → mkDecimal(i0, j).int = 0 → i0 = 0 ⊦ i = 0 |
mkDecimal(i / 10, abs(j) - 1).int = 0, i % 10 = 0, ∀ i0, j. i→n(i0) < i→n(i) → mkDecimal(i0, j).int = 0 → i0 = 0 ⊦ j = 0, i = 0