# A006757 (b-file synthesized from sequence entry) 0 0 1 8 2 10 3 11 4 12 5 16 6 32 7 54 8 97 9 183 10 334 11 636 12 1218 13 2339 14 4495 15 8807 16 17280 17 33924 18 66630 19 130921 20 259503