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%I #13 Jul 10 2015 18:17:21
%S 1,7,65,786,11814,212772,4468932,107259408,2896044336,86881692960,
%T 2867099496480,103215621790080,4025409728814720,169067214837239040,
%U 7608024754854048000,365185189540668672000,18624444687496892160000
%N a(n) = n! * 3^n * Sum_{i=1..n} 1/(i * 3^i).
%F E.g.f.: -log(1-x)/(1-3*x). - _Vladeta Jovovic_, Feb 07 2003
%F a(n) ~ n! * 3^n * log(3/2). - _Vaclav Kotesovec_, Oct 05 2013
%t Rest[CoefficientList[Series[-Log[1-x]/(1-3*x), {x, 0, 20}], x]* Range[0, 20]!] (* _Vaclav Kotesovec_, Oct 05 2013 *)
%Y Cf. A000254, A068102.
%K easy,nonn
%O 1,2
%A _Benoit Cloitre_, Apr 14 2002