# A149868 (b-file synthesized from sequence entry) 0 1 1 2 2 5 3 13 4 41 5 139 6 494 7 1771 8 6626 9 25477 10 99704 11 394028 12 1583784 13 6453726 14 26532762 15 109902780 16 459422070 17 1935495454 18 8199912534 19 34928922249 20 149648443966 21 644305507731 22 2785129360112 23 12087444079695 24 52667440706104 25 230264645786360 26 1009771676888315 27 4441475020721976 28 19591818756938375