# A149586 (b-file synthesized from sequence entry) 0 1 1 1 2 5 3 15 4 55 5 215 6 875 7 3533 8 14769 9 63025 10 271061 11 1171573 12 5125689 13 22634577 14 100374805 15 446869675 16 2001901659 17 9014772611 18 40708594111 19 184335519819 20 837884736507 21 3821043268147 22 17460417237311 23 79944561997591 24 366975174492475 25 1688354607241075 26 7779433515441811 27 35898846545834367