Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).
%I #14 Jan 30 2020 21:29:14
%S 1,36,1632,81600,4308480,235530240,13189693440,751812526080,
%T 43438057062400,2536782532444160,149439552820346880,
%U 8866746800673914880,529276578255612149760,31756594695336728985600
%N Related to octo-factorial numbers A045755.
%C Convolution of A034977(n-1) with A025753(n), n >= 1.
%H Michael De Vlieger, <a href="/A034996/b034996.txt">Table of n, a(n) for n = 1..555</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) = 8^(n-1)*A045755(n)/n!, A045755(n)=(8*n-7)!^8 := product(8*j-7, j=1..n); G.f. (-1+(1-64*x)^(-1/8))/8.
%F D-finite with recurrence: n*a(n) +8*(-8*n+7)*a(n-1)=0. - _R. J. Mathar_, Jan 28 2020
%t Rest@ CoefficientList[Series[(-1 + (1 - 64*x)^(-1/8))/8, {x, 0, 14}], x] (* _Michael De Vlieger_, Oct 13 2019 *)
%Y Cf. A045755, A034977, A025753, A034904.
%K easy,nonn
%O 1,2
%A _Wolfdieter Lang_