# A006385 (b-file synthesized from sequence entry) 0 1 1 2 2 4 3 14 4 52 5 248 6 1416 7 9172 8 66366 9 518868 10 4301350 11 37230364 12 333058463 13 3057319072 14 28656583950 15 273298352168 16 2645186193457 17 25931472185976