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A034996
Related to octo-factorial numbers A045755.
2
1, 36, 1632, 81600, 4308480, 235530240, 13189693440, 751812526080, 43438057062400, 2536782532444160, 149439552820346880, 8866746800673914880, 529276578255612149760, 31756594695336728985600
OFFSET
1,2
COMMENTS
Convolution of A034977(n-1) with A025753(n), n >= 1.
LINKS
Elżbieta Liszewska, Wojciech Młotkowski, Some relatives of the Catalan sequence, arXiv:1907.10725 [math.CO], 2019.
FORMULA
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.
D-finite with recurrence: n*a(n) +8*(-8*n+7)*a(n-1)=0. - R. J. Mathar, Jan 28 2020
MATHEMATICA
Rest@ CoefficientList[Series[(-1 + (1 - 64*x)^(-1/8))/8, {x, 0, 14}], x] (* Michael De Vlieger, Oct 13 2019 *)
CROSSREFS
KEYWORD
easy,nonn
STATUS
approved