# A075166 (b-file synthesized from sequence entry) 1 0 2 10 3 1010 4 1100 5 101010 6 101100 7 10101010 8 110100 9 110010 10 10101100 11 1010101010 12 10110100 13 101010101010 14 1010101100 15 10110010 16 111000 17 10101010101010 18 11001100 19 1010101010101010 20 1010110100 21 1010110010