Number of rooted trees with n nodes and omega-valency 3.

Terms

a(0) =0a(1) =0a(2) =0a(3) =0a(4) =1a(5) =1a(6) =6a(7) =11a(8) =42a(9) =92a(10) =294a(11) =720a(12) =2119a(13) =5460a(14) =15477a(15) =40989a(16) =114165a(17) =306980a(18) =848268a(19) =2301794a(20) =6341450a(21) =17308926a(22) =47659837a(23) =130628590a(24) =359924353a(25) =989642184a(26) =2730224431a(27) =7526539869a(28) =20795818601a(29) =57457010219