# A054149 (b-file synthesized from sequence entry) 1 1 2 14 3 84 4 410 5 1820 6 7648 7 31008 8 122584 9 475600 10 1818656 11 6874560 12 25742624 13 95645888 14 353032960 15 1295729664 16 4732541824 17 17211685120 18 62362187264 19 225201546240 20 810825419264 21 2911520685056 22 10429433085952