Number of (unlabeled) rooted trees with n leaf nodes and without unary nodes or outdegrees larger than four.

A292210

Number of (unlabeled) rooted trees with n leaf nodes and without unary nodes or outdegrees larger than four.

Terms

    a(0) =0a(1) =1a(2) =1a(3) =2a(4) =5a(5) =11a(6) =30a(7) =80a(8) =228a(9) =656a(10) =1945a(11) =5835a(12) =17808a(13) =54881a(14) =170951a(15) =536726a(16) =1697774a(17) =5403629a(18) =17295686a(19) =55630538a(20) =179726346a(21) =582942079a(22) =1897565974a(23) =6196973039a(24) =20297954197a(25) =66666192488a(26) =219505550167a(27) =724415274090

External references