# A148715 (b-file synthesized from sequence entry) 0 1 1 1 2 3 3 7 4 24 5 70 6 264 7 871 8 3427 9 12155 10 49471 11 184280 12 766809 13 2960544 14 12533294 15 49710976 16 213269188 17 864022759 18 3746852106 19 15440886655 20 67553784034 21 282328209955 22 1244366623559 23 5262103516706 24 23339496398318 25 99687654498177 26 444564154370691 27 1915211250088611 28 8581594213513618