Number of 4-ary rooted trees with n nodes and height exactly 4.

Terms

a(0) =0a(1) =0a(2) =0a(3) =0a(4) =1a(5) =3a(6) =8a(7) =18a(8) =35a(9) =65a(10) =114a(11) =194a(12) =316a(13) =510a(14) =793a(15) =1223a(16) =1839a(17) =2737a(18) =3984a(19) =5746a(20) =8123a(21) =11363a(22) =15615a(23) =21212a(24) =28336a(25) =37412a(26) =48597a(27) =62368a(28) =78810a(29) =98359