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%I #5 Dec 04 2018 17:39:49
%S 1,3,9,29,95,317,1076,3707,12935,45630,162486,583338,2109190,7674157,
%T 28077250,103234695,381260535,1413686490,5260849110,19642116150,
%U 73557465570,276224933010,1039922723424,3924250124142,14840700243830
%N Expansion of (1+x^3*C^2)*C^3, where C = (1-(1-4*x)^(1/2))/(2*x) is g.f. for Catalan numbers, A000108.
%t With[{c=(1-Sqrt[1-4x])/(2x)},CoefficientList[Series[(1+x^3 c^2)c^3,{x,0,30}],x]] (* _Harvey P. Dale_, Dec 04 2018 *)
%K nonn
%O 0,2
%A _N. J. A. Sloane_, Jun 06 2002