# A024311 (b-file synthesized from sequence entry) 1 0 2 0 3 1 4 7 5 30 6 132 7 559 8 2416 9 10483 10 46072 11 204155 12 912779 13 4110644 14 18636572 15 84985825 16 389586145 17 1794268460 18 8298524480 19 38527095859 20 179487051589 21 838820171722 22 3931498431052 23 18475618863389 24 87036535974062 25 410947146076475