# A149615 (b-file synthesized from sequence entry) 0 1 1 1 2 5 3 15 4 63 5 243 6 1019 7 4273 8 18309 9 79537 10 347953 11 1540517 12 6848389 13 30699769 14 138103437 15 624792087 16 2835583031 17 12920696755 18 59038536867 19 270570671015 20 1242960486199 21 5723341739351 22 26406806760755 23 122069901607203 24 565252421469507 25 2621600015540423 26 12176517064331299 27 56632633782716711