Matula-Goebel tree number of the binomial tree of n vertices.

Terms

a(0) =1a(1) =2a(2) =4a(3) =6a(4) =12a(5) =18a(6) =42a(7) =78a(8) =156a(9) =234a(10) =546a(11) =1014a(12) =2886a(13) =4758a(14) =14118a(15) =30966a(16) =61932a(17) =92898a(18) =216762a(19) =402558a(20) =1145742a(21) =1888926a(22) =5604846a(23) =12293502a(24) =28210026a(25) =45860646a(26) =121727346a(27) =249864654a(28) =813198126a(29) =1423166394