| j0 + j1 - 2 ^ i = ~1 * 2 ^ i + j0 + j1, 0 < i, 0 ≤ i, 0 ≤ i0, 0 ≤ j1, j1 < 2 ^ i, 2 ^ (i - 1) ≤ j1, 0 < i, j0 < 0 ⊦ cast(i, j0 + j1) = cast(i, j0 + j1 - 2 ^ i) |
0 < i, 0 ≤ i, 0 ≤ i0, 0 ≤ j1, j1 < 2 ^ i, 2 ^ (i - 1) ≤ j1, 0 < i, j0 < 0 ⊦ cast(i, j0 + j1) = cast(i, ~1 * 2 ^ i + j0 + j1)