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%I #17 Jan 30 2020 21:29:14
%S 1,28,980,37730,1531838,64337196,2766499428,121034349975,
%T 5365856182225,240390356963680,10861273400995360,494187939745288880,
%U 22618601857572837200,1040455685448350511200,48069052667713793617440
%N Related to sept-factorial numbers A045754.
%C Convolution of A034835(n-1) with A025752(n), n >= 1.
%H Michael De Vlieger, <a href="/A034904/b034904.txt">Table of n, a(n) for n = 1..594</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) = 7^(n-1)*A045754(n)/n!, A045754(n)=(7*n-6)(!^7) := product(7*j-6, j=1..n); G.f. (-1+(1-49*x)^(-1/7))/7.
%F D-finite with recurrence: n*a(n) +7*(-7*n+6)*a(n-1)=0. - _R. J. Mathar_, Jan 28 2020
%t CoefficientList[Series[(Power[1-49x, (-7)^-1]-1)/7,{x,0,30}],x] (* _Harvey P. Dale_, Aug 23 2011 *)
%Y Cf. A045754, A034835, A025752.
%K easy,nonn
%O 1,2
%A _Wolfdieter Lang_
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