# A150137 (b-file synthesized from sequence entry) 0 1 1 2 2 6 3 20 4 73 5 271 6 1064 7 4212 8 17196 9 70596 10 296012 11 1245082 12 5318268 13 22764797 14 98594587 15 427635358 16 1872119304 17 8204325414 18 36227766180 19 160091182728 20 711920762932 21 3167656255528 22 14169825390905 23 63412119597744 24 285085092838761 25 1282074973042071 26 5788791384218925 27 26143617239786913