# A149968 (b-file synthesized from sequence entry) 0 1 1 2 2 5 3 16 4 55 5 188 6 674 7 2471 8 9067 9 33926 10 128156 11 484224 12 1847218 13 7084777 14 27186054 15 104885416 16 405958461 17 1572023508 18 6108058902 19 23783305717 20 92648913045 21 361724652715 22 1414358846767 23 5532545855330 24 21675406458263 25 85011660185348 26 333545750611017 27 1310157468147696 28 5150459680441075