| j < 0, 1 + # int2bits(~ j) < # int2bits(~ j - 1), 0 ≤ 2 ^ i * (2 ^ n→i(# int2bits(~ j)) + j) + j0, 0 ≤ i, 0 < 2 ^ i + j0, j * 2 ^ i + j0 < 0, 0 < i, j < 0, j0 < 0, 0 < 2 ^ (i - 1) + j0 ⊦ j + 2 ^ n→i(# int2bits(~ j)) = 0, sgn(uint2bits(2 ^ i * (2 ^ n→i(# int2bits(~ j)) + j) + j0).rest) = int2bits(j - 1) + fillsgn(i→n(i), int2bits(j0)), j0 = 0, j * 2 ^ i + j0 = 0 |
1 + # int2bits(~ j) < # int2bits(~(j + 1)), 0 < 2 ^ (i - 1) + j0, j0 < 0, j < 0, 0 < i, j * 2 ^ i + j0 < 0, 0 < 2 ^ i + j0, 0 ≤ i, 0 ≤ 2 ^ i * (2 ^ n→i(# int2bits(~ j)) + j) + j0 ⊦ j * 2 ^ i + j0 = 0, j0 = 0, sgn(uint2bits(2 ^ i * (2 ^ n→i(# int2bits(~ j)) + j) + j0).rest) = int2bits(j - 1) + fillsgn(i→n(i), int2bits(j0)), j + 2 ^ n→i(# int2bits(~ j)) = 0
Used simplifier rules: int2bits-not-empty: ⊦ int2bits(j) ≠ [];% ⊦ # bits = 0 ↔ bits = [];% ⊦ m < n → n ≠ 0; (forward)% ⊦ ~ i - j = ~(i + j);% ⊦ i + j = j + i;% ⊦ i + j + i0 = (i + j) + i0;