Number of graphical partitions of biconnected graphs with n nodes.

Terms

a(0) =1a(1) =3a(2) =9a(3) =34a(4) =125a(5) =473a(6) =1779a(7) =6732a(8) =25492a(9) =96927a(10) =369463a(11) =1412700a(12) =5415117a(13) =20807502a(14) =80120350a(15) =309106496a(16) =1194609429a(17) =4624160156a(18) =17925278497a(19) =69578272204a(20) =270401326899