# A149835 (b-file synthesized from sequence entry) 0 1 1 2 2 4 3 10 4 30 5 96 6 324 7 1138 8 4134 9 15464 10 59198 11 230678 12 913916 13 3672582 14 14940794 15 61426632 16 254982076 17 1067415522 18 4502824810 19 19124778850 20 81738521776 21 351324672662 22 1517933308038 23 6589522925548 24 28732010239624 25 125785366412276 26 552750320877912 27 2437456478786392 28 10783477702624244