Number of "hyperforests" on n unlabeled nodes, i.e., hypergraphs that have no cycles, assuming that each edge contains at least two vertices.

A134955

Number of "hyperforests" on n unlabeled nodes, i.e., hypergraphs that have no cycles, assuming that each edge contains at least two vertices.

Terms

    a(0) =1a(1) =1a(2) =2a(3) =4a(4) =9a(5) =20a(6) =50a(7) =128a(8) =351a(9) =1009a(10) =3035a(11) =9464a(12) =30479a(13) =100712a(14) =340072a(15) =1169296a(16) =4082243a(17) =14438577a(18) =51643698a(19) =186530851a(20) =679530937a(21) =2494433346a(22) =9219028889a(23) =34280914106a(24) =128179985474a(25) =481694091291

External references