Triangle of rooted identity trees with n nodes and k leaves.

Terms

a(0) =1a(1) =1a(2) =1a(3) =1a(4) =1a(5) =1a(6) =2a(7) =1a(8) =4a(9) =1a(10) =1a(11) =6a(12) =5a(13) =1a(14) =9a(15) =13a(16) =2a(17) =1a(18) =12a(19) =28a(20) =11a(21) =1a(22) =16a(23) =53a(24) =40a(25) =3a(26) =1a(27) =20a(28) =91a(29) =109