| mkDecimal(i / 10, abs(j) - 1) = mkDecimal(i0, j0) ↔ i / 10 * 10 ^ abs(j0) = i0 * 10 ^ abs(abs(j) - 1), i % 10 = 0, ∀ i1, i2, j, j0. i→n(i1) + i→n(i2) < i→n(i) + i→n(i0) → true → (mkDecimal(i1, j) = mkDecimal(i2, j0) ↔ i1 * 10 ^ abs(j0) = i2 * 10 ^ abs(j)) ⊦ j = 0, mkDecimal(i / 10, abs(j) - 1) = mkDecimal(i0, j0) ↔ i * 10 ^ abs(j0) = i0 * 10 ^ abs(j) |
i % 10 = 0, mkDecimal(i / 10, abs(j) - 1) = mkDecimal(i0, j0) ↔ i / 10 * 10 ^ abs(j0) = i0 * 10 ^ (abs(j) - 1), ∀ i1, i2, j, j0. i→n(i1) + i→n(i2) < i→n(i) + i→n(i0) → true → (mkDecimal(i1, j) = mkDecimal(i2, j0) ↔ i1 * 10 ^ abs(j0) = i2 * 10 ^ abs(j)) ⊦ j = 0, mkDecimal(i / 10, abs(j) - 1) = mkDecimal(i0, j0) ↔ i * 10 ^ abs(j0) = i0 * 10 ^ abs(j)
Used simplifier rules: abs-abs: ⊦ j ≠ 0 → abs(abs(j) - 1) = abs(j) - 1; from specification int-abs