# A049947 (b-file synthesized from sequence entry) 1 1 2 1 3 4 4 7 5 20 6 34 7 74 8 175 9 491 10 808 11 1622 12 3271 13 6683 14 13999 15 30461 16 71650 17 200951 18 330253 19 660512 20 1321051 21 2642243 22 5285119 23 10572701 24 21156130 25 42369911 26 84998425 27 170987648 28 345939364 29 707749739 30 1479341773 31 3219624485