# A006755 (b-file synthesized from sequence entry) 0 0 1 2 2 3 3 4 4 8 5 14 6 25 7 47 8 86 9 164 10 314 11 603 12 1159 13 2271 14 4456 15 8748 16 17182 17 33761 18 66919 19 132679 20 263087