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