| i→n(i) ≤ # int2bits(j / 2 ^ i) + # fillsgn(i→n(i) + 1, int2bits(j % 2 ^ i)).rest, 2 ^ i ≤ j, 0 ≤ 2 ^ (i - 1) + j, j % 2 ^ i < j, 2 ^ (i - 1) ≤ j, 0 ≤ j, 0 < i, j % 2 ^ i < 2 ^ (i - 1) ⊦ i→n(i) = # fillsgn(i→n(i) + 1, int2bits(j % 2 ^ i)).rest, bits2int(lastn(i→n(i), int2bits(j / 2 ^ i) + fillsgn(i→n(i) + 1, int2bits(j % 2 ^ i)).rest)) = j % 2 ^ i |
⊦ bits ≠ [] → # bits.rest = (# bits)-1
fillsgn(i→n(i) + 1, int2bits(j % 2 ^ i)) ≠ [], i→n(i) ≤ # int2bits(j / 2 ^ i) + (# fillsgn(i→n(i) + 1, int2bits(j % 2 ^ i)))-1, 2 ^ i ≤ j, 0 ≤ 2 ^ (i - 1) + j, j % 2 ^ i < j, 2 ^ (i - 1) ≤ j, 0 ≤ j, 0 < i, j % 2 ^ i < 2 ^ (i - 1) ⊦ i→n(i) = (# fillsgn(i→n(i) + 1, int2bits(j % 2 ^ i)))-1, bits2int(lastn(i→n(i), int2bits(j / 2 ^ i) + fillsgn(i→n(i) + 1, int2bits(j % 2 ^ i)).rest)) = j % 2 ^ i
Used simplifier rules: ⊦ fillsgn(n, bits) = [] ↔ bits = [] ∧ n = 0;% ⊦ int2bits(j) ≠ []; Used terms: fillsgn(i→n(i) + 1, int2bits(j % 2 ^ i))