| ∀ bits1, bits. # bits1 < # bits0 → true → bits = [] ∨ bits1 = [] ∨ sgn(bitsand(sgn(bits), bits1)) = sgn(bitsand(bits, bits1)) ⊦ sgn(bitsand(sgn(bits), bits0)) = sgn(bitsand(bits, bits0)), bits0 = [], bits = [], bits0 = true ', bits0 = false ', bits ≠ bits.first ' ∧ bits0 ≠ bits0.first ' |
⊦ bits0 ≠ [] ∧ bits = true ' → bitsand(bits, bits0) = bits0
¬(bits0 ≠ [] ∧ bits = true '), ∀ bits1, bits. # bits1 < # bits0 → true → bits = [] ∨ bits1 = [] ∨ sgn(bitsand(sgn(bits), bits1)) = sgn(bitsand(bits, bits1)) ⊦ sgn(bitsand(sgn(bits), bits0)) = sgn(bitsand(bits, bits0)), bits0 = [], bits = [], bits0 = true ', bits0 = false ', bits ≠ bits.first ' ∧ bits0 ≠ bits0.first '
Used simplifier rules: and-onel-01: ⊦ bits ≠ [] → bitsand(true ', bits) = bits;% ⊦ sgn(boolvar ') = boolvar ';% ⊦ boolvar ' ≠ []; Used terms: bits0, bits