Number of rooted trees with n nodes with every leaf at height 3.

Terms

a(0) =1a(1) =1a(2) =2a(3) =3a(4) =5a(5) =7a(6) =12a(7) =18a(8) =27a(9) =42a(10) =64a(11) =96a(12) =146a(13) =219a(14) =327a(15) =491a(16) =730a(17) =1084a(18) =1608a(19) =2376a(20) =3500a(21) =5154a(22) =7563a(23) =11076a(24) =16193a(25) =23625a(26) =34395a(27) =50005a(28) =72550a(29) =105089