| # bits0 = 1, ∀ n, bits, bits1. # bits1 < 1 → true → bits = [] ∨ bits1 = [] ∨ fillsgn(n, bitsand(fillsgn(n, bits), bits1)) = fillsgn(n, bitsand(bits, bits1)) ⊦ fillsgn(n, bitsand(fillsgn(n, bits), bits0)) = fillsgn(n, bitsand(bits, bits0)), bits0 = [], bits = [], # bits = 1 |
⊦ bits ≠ [] ∧ bits0 = true ' → bitsand(bits, bits0) = bits
¬(bits ≠ [] ∧ bits0 = true '), # bits0 = 1, ∀ n, bits, bits1. # bits1 < 1 → true → bits = [] ∨ bits1 = [] ∨ fillsgn(n, bitsand(fillsgn(n, bits), bits1)) = fillsgn(n, bitsand(bits, bits1)) ⊦ fillsgn(n, bitsand(fillsgn(n, bits), bits0)) = fillsgn(n, bitsand(bits, bits0)), bits0 = [], bits = [], # bits = 1
bits ≠ [] ∧ bits0 = true ', # bits0 = 1, ∀ n, bits, bits1. # bits1 < 1 → true → bits = [] ∨ bits1 = [] ∨ fillsgn(n, bitsand(fillsgn(n, bits), bits1)) = fillsgn(n, bitsand(bits, bits1)) ⊦ fillsgn(n, bitsand(fillsgn(n, bits), bits0)) = fillsgn(n, bits), bits0 = [], bits = [], # bits = 1
Used terms: bits0, bits