| 1 < # bits0 ∧ 1 < # bits, ∀ bits1, bits. # bits1 < # bits0 → true → bits = [] ∨ bits1 = [] ∨ bitsand(bits, bits1) = bitsand(bits1, bits) ⊦ bits0 = [], bits = [], bitsand(bits.butlast, bits0.butlast) + (bits.last ∧ bits0.last)' = bitsand(bits0.butlast, bits.butlast) + (bits0.last ∧ bits.last), bits = bits.first ', bits0 = bits0.first ' |
∀ bits1, bits. # bits1 < # bits0 → true → bits = [] ∨ bits1 = [] ∨ bitsand(bits, bits1) = bitsand(bits1, bits) ⊦ bits = bits.first ', bits0 = bits0.first ', bits0 = [], bits = [], bitsand(bits.butlast, bits0.butlast) + (bits.last ∧ bits0.last)' = bitsand(bits0.butlast, bits.butlast) + (bits0.last ∧ bits.last)'
Used simplifier rules: ⊦ (bits + bits0) + bits1 = bits + bits0 + bits1;% ⊦ bits + [] = bits;% ⊦ boolvar + bits = boolvar ' + bits;% ⊦ # bits = 1 ↔ bits = bits.first + [];% ⊦ # bits = 0 ↔ bits = [];% ⊦ 1 < m ↔ ¬(m = 0 ∨ m = 1);% ⊦ bits + boolvar = bits + boolvar ';