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%I #17 Jan 30 2020 21:29:14
%S 1,45,2565,161595,10762227,742593663,52511980455,3780862592760,
%T 276002969271480,20369019132235224,1516566060845513496,
%U 113742454563413512200,8583180609746819651400,651095557682223033556200
%N Related to 9-factorial numbers A045756.
%C Convolution of A035024(n-1) with A025754(n), n >= 1.
%H Michael De Vlieger, <a href="/A035097/b035097.txt">Table of n, a(n) for n = 1..526</a>
%H Elżbieta Liszewska, Wojciech Młotkowski, <a href="https://arxiv.org/abs/1907.10725">Some relatives of the Catalan sequence</a>, arXiv:1907.10725 [math.CO], 2019.
%H <a href="/index/Fa#factorial">Index entries for sequences related to factorial numbers</a>
%F a(n) = 9^(n-1)*A045756(n)/n!, A045756(n)=(9*n-8)(!^9) := product(9*j-8, j=1..n); G.f. (-1+(1-81*x)^(-1/9))/9.
%F D-finite with recurrence: n*a(n) +9*(-9*n+8)*a(n-1)=0. - _R. J. Mathar_, Jan 28 2020
%t CoefficientList[Series[(1/(1-81 x)^(1/9)-1)/(9 x),{x,0,20}],x] (* _Harvey P. Dale_, May 14 2011 *)
%Y Cf. A045756, A035024, A025754, A034996.
%K easy,nonn
%O 1,2
%A _Wolfdieter Lang_