| # bits = n + 1 + # bits1, # bits1 < # bits, ∀ bits0, bits, n. # bits0 < # bits1 → # bits = n + 1 + # bits0 ∧ # bits0 < # bits → bits = [] ∨ bitsand(bits, true ' + bits0) = (true ' + mklist(true, n)) + bits0 ∨ false ∈ bits ⊦ bitsand(bits, true ' + bits1) = (true ' + mklist(true, n)) + bits1, bits = [], false ∈ bits |
⊦ 1 < # bits ∧ 1 < # bits0 → bitsand(bits, bits0) = bitsand(bits.butlast, bits0.butlast) + (bits.last ∧ bits0.last)
¬(1 < # bits ∧ 1 < #(true ' + bits1)), # bits = n + 1 + # bits1, # bits1 < # bits, ∀ bits0, bits, n. # bits0 < # bits1 → # bits = n + 1 + # bits0 ∧ # bits0 < # bits → bits = [] ∨ bitsand(bits, true ' + bits0) = (true ' + mklist(true, n)) + bits0 ∨ false ∈ bits ⊦ bitsand(bits, true ' + bits1) = (true ' + mklist(true, n)) + bits1, bits = [], false ∈ bits
1 < # bits ∧ 1 < #(true ' + bits1), # bits = n + 1 + # bits1, # bits1 < # bits, ∀ bits0, bits, n. # bits0 < # bits1 → # bits = n + 1 + # bits0 ∧ # bits0 < # bits → bits = [] ∨ bitsand(bits, true ' + bits0) = (true ' + mklist(true, n)) + bits0 ∨ false ∈ bits ⊦ bitsand(bits.butlast, (true ' + bits1).butlast) + (bits.last ∧ (true ' + bits1).last) = (true ' + mklist(true, n)) + bits1, bits = [], false ∈ bits
Used terms: true ' + bits1, bits