| ⊦ bits = [], bits0 = [], bits2int(bitsor(bits, bits0) + bits1) = bits2int(true ' + bits1), false ∈ bits |
⊦ ¬ false ∈ bits ∧ ¬ bits0.first ∧ bits ≠ [] ∧ bits0 ≠ [] → bitsor(bits, bits0) = bits
¬(¬ false ∈ bits ∧ ¬ bits0.first ∧ bits ≠ [] ∧ bits0 ≠ []) ⊦ bits = [], bits0 = [], bits2int(bitsor(bits, bits0) + bits1) = bits2int(true ' + bits1), false ∈ bits
¬ false ∈ bits ∧ ¬ bits0.first ∧ bits ≠ [] ∧ bits0 ≠ [] ⊦ bits = [], bits0 = [], bits2int(bits + bits1) = bits2int(true ' + bits1), false ∈ bits
Used terms: bits0, bits