| ¬(1 < # bits0 ∧ 1 < # bits2), # bits0 = # bits2, ∀ bits1, bits, bits2, bits3. # bits3 < # bits0 → # bits3 = # bits2 → bits = [] ∨ bits3 = [] ∨ bits1 = [] ∨ bitsxor(bits + bits3, bits1 + bits2) = bitsxor(bits, bits1) + bitsxor(bits3, bits2) ⊦ # bits + # bits2 = 0, # bits1 + # bits2 = 0, bits2 = [], bits1 = [], bits0 = [], bits = [], bitsxor(bits + bits0.butlast, bits1 + bits2.butlast) + (¬(bits0.last ↔ bits2.last))' = bitsxor(bits, bits1) + bitsxor(bits0, bits2) |
# bits2 = 1, # bits0 = 1, ∀ bits1, bits, bits2, bits3. # bits3 < 1 → # bits3 = # bits2 → bits = [] ∨ bits3 = [] ∨ bits1 = [] ∨ bitsxor(bits + bits3, bits1 + bits2) = bitsxor(bits, bits1) + bitsxor(bits3, bits2) ⊦ bits2 = [], bits1 = [], bits0 = [], bits = [], bitsxor(bits + bits0.butlast, bits1 + bits2.butlast) + (¬(bits0.last ↔ bits2.last))' = bitsxor(bits, bits1) + bitsxor(bits0, bits2)
Used simplifier rules: ⊦ m + n = n + m;% ⊦ (m + n0) + n1 = m + n0 + n1;% ⊦ m + 1 ≠ 0;% ⊦ # bits = 0 ↔ bits = [];% ⊦ 1 < m ↔ ¬(m = 0 ∨ m = 1);