# A225958 (b-file synthesized from sequence entry) 0 1 1 2 2 10 3 44 4 134 5 468 6 1524 7 4584 8 13862 9 40566 10 114880 11 321052 12 879092 13 2360156 14 6248864 15 16297384 16 41902454 17 106437600 18 267149022 19 662979572 20 1628437160 21 3960377672 22 9541519732 23 22786066280 24 53958062564 25 126750346970 26 295476011176 27 683776368416 28 1571299804688