M-type rooted trees on n nodes.

Terms

a(0) =1a(1) =4a(2) =17a(3) =83a(4) =432a(5) =2416a(6) =14093a(7) =85188a(8) =528234a(9) =3343420a(10) =21508182a(11) =140225532a(12) =924444270a(13) =6152191399a(14) =41275242100a(15) =278865583963