Number of rooted trees with n nodes with every leaf at the same height.

Terms

a(0) =1a(1) =1a(2) =2a(3) =3a(4) =5a(5) =7a(6) =12a(7) =17a(8) =28a(9) =42a(10) =68a(11) =103a(12) =168a(13) =260a(14) =420a(15) =665a(16) =1075a(17) =1716a(18) =2787a(19) =4489a(20) =7304a(21) =11849a(22) =19333a(23) =31504a(24) =51561a(25) =84347a(26) =138378a(27) =227096a(28) =373445a(29) =614441