Total height of trees with n nodes.

Terms

a(0) =0a(1) =1a(2) =3a(3) =8a(4) =22a(5) =58a(6) =158a(7) =425a(8) =1161a(9) =3175a(10) =8751a(11) =24192a(12) =67239a(13) =187459a(14) =524579a(15) =1472086a(16) =4142639a(17) =11685501a(18) =33036492a(19) =93583873a(20) =265589158a(21) =754998424a(22) =2149588878a(23) =6128914829a(24) =17497927510a(25) =50017546412a(26) =143137957590a(27) =410062891934