| # 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) |
⊦ 1 < # bits ∧ 1 < # bits0 → bitsxor(bits, bits0) = bitsxor(bits.butlast, bits0.butlast) + (¬(bits.last ↔ bits0.last))
¬(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)
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.butlast, bits2.butlast) + (¬(bits0.last ↔ bits2.last)))
Used terms: bits2, bits0