a=10 b=0 N=40 nonextendable solution #1 (g=640): 0: 0000000000 1: 0000000000 2: 0000011111 3: 0000101111 4: 0001110011 5: 0010110011 6: 0011001101 7: 0011001110 8: 0011110100 9: 0011111000 10: 0100111100 11: 0101010101 12: 0101011010 13: 0101100110 14: 0101101001 15: 0110010110 16: 0110011001 17: 0110100101 18: 0110101010 19: 0111000011 20: 1000111100 21: 1001010110 22: 1001011001 23: 1001100101 24: 1001101010 25: 1010010101 26: 1010011010 27: 1010100110 28: 1010101001 29: 1011000011 30: 1100000111 31: 1100001011 32: 1100110001 33: 1100110010 34: 1101001100 35: 1110001100 36: 1111010000 37: 1111100000 38: 1111111111 39: 1111111111 nonextendable solution #2 (g=1440): 0: 0000000000 1: 0000000000 2: 0000011111 3: 0001100111 4: 0001111001 5: 0010101110 6: 0010110011 7: 0011001101 8: 0011011010 9: 0011110100 10: 0100101011 11: 0100111100 12: 0101001110 13: 0101010101 14: 0101110010 15: 0110010110 16: 0110011001 17: 0110100101 18: 0111000011 19: 0111101000 20: 1000101101 21: 1000110110 22: 1001010011 23: 1001011100 24: 1001101010 25: 1010001011 26: 1010010101 27: 1010111000 28: 1011000110 29: 1011100001 30: 1100000111 31: 1100011010 32: 1100110001 33: 1101001001 34: 1101100100 35: 1110001100 36: 1110100010 37: 1111010000 38: 1111111111 39: 1111111111 That was all - 2 solutions