| ¬ bitsand(sgn(lastn(8, fillsgn(8, int2bits(i)))), int2bits(j)) ≠ [], lastn(8, fillsgn(8, int2bits(i))) ≠ [] ⊦ band(i, j) = bits2int(bitsand(sgn(lastn(8, fillsgn(8, int2bits(i)))), int2bits(j))), b2i(i2b(band(i, j))) = bits2int(lastn(8, fillsgn(8, int2bits(bits2int(bitsand(sgn(lastn(8, fillsgn(8, int2bits(i)))), int2bits(j))))))) |
bitsand(sgn(lastn(8, fillsgn(8, int2bits(i)))), int2bits(j)) = [] ⊦ band(i, j) = bits2int([]), b2i(i2b(band(i, j))) = bits2int(lastn(8, fillsgn(8, int2bits(bits2int([])))))
Used simplifier rules: ⊦ lastn(n, bits) = [] ↔ n = 0;