# A090856 (b-file synthesized from sequence entry) 0 1 1 7 2 27 3 104 4 378 5 1327 6 4553 7 15351 8 51072 9 168147 10 548915 11 1779377 12 5734022 13 18384612 14 58688163 15 186632570 16 591509670 17 1869118923 18 5890466415 19 18518945789 20 58094637801 21 181884111404 22 568416743474 23 1773443888599