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A181161 Numerator in abs(binomial(-1/8,n)). 0
1, 1, 9, 51, 1275, 8415, 115005, 805035, 45886995, 331406075, 4838528695, 35629165845, 1056998586735, 7886835608715, 118302534130725, 891212423784795, 107836703277960195, 818290277815109715 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Table of n, a(n) for n=0..17.

FORMULA

a(n) = 2^(e_2((2*n)!)-n)/n! * Product[8k+1,{k,0,n-1}] where e_2((2n)!) is the highest power of 2 that divides (2*n)! (sequence A005187)

MATHEMATICA

w[n_] := Numerator[Binomial[(-1/8, n](-1)^n]

Table[w1[n], {n, 0, 12}]

CROSSREFS

A004130

Sequence in context: A210054 A272393 A231748 * A152580 A197722 A172470

Adjacent sequences:  A181158 A181159 A181160 * A181162 A181163 A181164

KEYWORD

nonn

AUTHOR

Emanuele Munarini, Jan 25 2011

STATUS

approved

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Last modified February 27 09:59 EST 2020. Contains 332304 sequences. (Running on oeis4.)