A038061 - OEIS

%I #17 Feb 14 2017 11:07:38

%S 3,18,243,5184,151875,5668704,257298363,13759414272,847288609443,

%T 59049000000000,4594736955793347,394865111526801408,

%U 37144672966729275363,3796313155316599873536,418886580596209716796875

%N a(n) = 3^n*n^(n-1).

%C Labeled rooted trees with 3-colored nodes.

%H <a href="/index/Ro#rooted">Index entries for sequences related to rooted trees</a>

%F E.g.f. B(3x) where B(x) is e.g.f. of A000169.

%p A038061:=n->3^n*n^(n-1): seq(A038061(n), n=1..20); # _Wesley Ivan Hurt_, Feb 13 2017

%t Table[3^n n^(n-1),{n,20}] (* _Harvey P. Dale_, Aug 24 2012 *)

%Y Cf. A000169, A038055-A038062.

%K nonn

%O 1,1

%A _Christian G. Bower_, Jan 04 1999

%E New description from _Vladeta Jovovic_, Mar 08 2003