# A162920 (b-file synthesized from sequence entry) 0 1 1 3 2 6 3 12 4 21 5 36 6 63 7 108 8 186 9 321 10 552 11 951 12 1638 13 2820 14 4857 15 8364 16 14403 17 24804 18 42714 19 73557 20 126672 21 218139 22 375654 23 646908 24 1114029 25 1918452 26 3303735 27 5689308 28 9797466 29 16872057 30 29055096 31 50035311 32 86164998 33 148383348