# A271270 (b-file synthesized from sequence entry) 0 1 1 1 2 2 3 5 4 14 5 43 6 145 7 536 8 2157 9 9371 10 43630 11 216397 12 1137703 13 6313675 14 36848992 15 225464838 16 1442216870 17 9620746697 18 66781675113 19 481413175433 20 3597627996006 21 27825925290597 22 222422033403527 23 1834910286704787 24 15603508329713182 25 136616625732498989