# A150104 (b-file synthesized from sequence entry) 0 1 1 2 2 6 3 19 4 68 5 255 6 989 7 3955 8 16147 9 67057 10 282495 11 1203909 12 5180147 13 22480686 14 98268169 15 432231388 16 1911944862 17 8499084865 18 37945861008 19 170096408313 20 765203667592 21 3453498192794 22 15632819897677 23 70956387986424 24 322865559744975 25 1472499460157086 26 6729929928075598 27 30818993591307189