Number of unlabeled balanced semi-binary rooted trees with n nodes.

Terms

a(0) =1a(1) =1a(2) =2a(3) =2a(4) =3a(5) =4a(6) =6a(7) =7a(8) =10a(9) =13a(10) =19a(11) =25a(12) =35a(13) =46a(14) =65a(15) =88a(16) =124a(17) =171a(18) =242a(19) =334a(20) =470a(21) =653a(22) =921a(23) =1287a(24) =1822a(25) =2565a(26) =3640a(27) =5144a(28) =7311a(29) =10360