# A121092 (b-file synthesized from sequence entry) 0 1 1 1 2 4 3 11 4 41 5 141 6 533 7 1952 8 7320 9 27287 10 102322 11 383616 12 1442145 13 5428213 14 20472232 15 77333718 16 292638204 17 1109160702 18 4210704579 19 16009469632 20 60959141474 21 232440067211 22 887498464664 23 3392984209344 24 12987589660706