# A149572 (b-file synthesized from sequence entry) 0 1 1 1 2 5 3 13 4 63 5 203 6 999 7 3587 8 17759 9 67651 10 336021 11 1331219 12 6625527 13 26986373 14 134486323 15 559145055 16 2788924975 17 11780888151 18 58797042195 19 251528398701 20 1255897609137 21 5428250453879 22 27112257364177 23 118192158415853 24 590469598600839 25 2592741636999165 26 12955252325160873 27 57239205344554295