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 A181161 Numerator in abs(binomial(-1/8,n)). 0

%I

%S 1,1,9,51,1275,8415,115005,805035,45886995,331406075,4838528695,

%T 35629165845,1056998586735,7886835608715,118302534130725,

%U 891212423784795,107836703277960195,818290277815109715

%N Numerator in abs(binomial(-1/8,n)).

%F 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)

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

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

%Y A004130

%K nonn

%O 0,3

%A _Emanuele Munarini_, Jan 25 2011

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Last modified December 3 18:19 EST 2021. Contains 349467 sequences. (Running on oeis4.)