a=8 b=0 N=16 solution #1 (g=21504): 0: 00000000 1: 00001111 2: 00110011 3: 00111100 4: 01010101 5: 01011010 6: 01100110 7: 01101001 8: 10010110 9: 10011001 10: 10100101 11: 10101010 12: 11000011 13: 11001100 14: 11110000 15: 11111111 That was all - 1 solution