# A148586 (b-file synthesized from sequence entry) 0 1 1 1 2 3 3 6 4 20 5 54 6 189 7 594 8 2143 9 7387 10 27380 11 100067 12 379944 13 1443052 14 5599659 15 21844255 16 86394133 17 343768974 18 1381731518 19 5584666966 20 22751462847 21 93150610255 22 383799188075 23 1588579086014 24 6608521212364 25 27608162197782 26 115812839302734 27 487692262398236 28 2060876813337521