| bits2bytes(firstn(n0 + 8, bits)) = bits2bytes(firstn(8, bits)) + bits2bytes(restn(8, firstn(n0 + 8, bits))), # bits = 16 + n0, n0 % 8 = 0, ∀ bits0. # bits0 < (n0 + 8) + 8 → true → # bits0 % 8 = 0 ∧ 8 < # bits0 → bits2bytes(bits0) = bits2bytes(firstn(8, bits0)) + bits2bytes(restn(8, bits0)) ⊦ n0 = 0, bits = [], bits2bytes(firstn(n0 + 8, bits)) + i2b(bits2int(lastn(8, bits))) ' = bits2bytes(firstn(8, bits)) + bits2bytes(firstn(n0, restn(8, bits))) + i2b(bits2int(lastn(8, restn(8, bits)))) ' |
# bits = 16 + n0, n0 % 8 = 0, ∀ bits0. # bits0 < (n0 + 8) + 8 → true → # bits0 % 8 = 0 ∧ 8 < # bits0 → bits2bytes(bits0) = bits2bytes(firstn(8, bits0)) + bits2bytes(restn(8, bits0)) ⊦ n0 = 0, bits = [], (bits2bytes(firstn(8, bits)) + bits2bytes(restn(8, firstn(n0 + 8, bits)))) + i2b(bits2int(lastn(8, bits))) ' = bits2bytes(firstn(8, bits)) + bits2bytes(firstn(n0, restn(8, bits))) + i2b(bits2int(lastn(8, restn(8, bits)))) '