Number of trees of diameter 8.

Terms

a(0) =1a(1) =4a(2) =19a(3) =66a(4) =219a(5) =645a(6) =1813a(7) =4802a(8) =12265a(9) =30198a(10) =72396a(11) =169231a(12) =387707a(13) =871989a(14) =1930868a(15) =4215615a(16) =9091410a(17) =19389327a(18) =40944999a(19) =85691893a(20) =177898521a(21) =366614456a(22) =750494796a(23) =1526979694a(24) =3089556090a(25) =6219191608a(26) =12460307373a(27) =24856533408a(28) =49387348955a(29) =97765283686