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%I #23 Nov 25 2016 05:22:40
%S 1,16,230,3480,57379,1038016,20570444,444647600,10431670821,
%T 264300628944,7198061846898,209814739262856,6520139954328519,
%U 215245451727154944,7524314127912551832,277705505168550027360,10792700030471840300745,440604294676004639627280
%N Coefficient of x^3 in expansion of (x+1)*(x+3)*...*(x+2*n-1).
%C Equals fourth left hand column of A161198 triangle divided by 8. - _Johannes W. Meijer_, Jun 08 2009
%H G. C. Greubel, <a href="/A028340/b028340.txt">Table of n, a(n) for n = 3..400</a>
%F a(n) = Sum_{i=k+1..n} (-1)^(k+1-i)*2^(n-1)*binomial(i-1, k)*s1(n, i) with k = 3, where s1(n, i) are unsigned Stirling numbers of the first kind. - Victor Adamchik (adamchik(AT)ux10.sp.cs.cmu.edu), Jan 23 2001
%F E.g.f.: -(log(1-2*x))^3/( 48*sqrt(1-2*x) ). - _Vladeta Jovovic_, Feb 19 2003
%t Table[Coefficient[Product[x + 2*k - 1, {k, 1, n}], x, 3], {n,3,50}] (* _G. C. Greubel_, Nov 24 2016 *)
%o (PARI) a(n) = polcoeff(prod(k=1, n, x+2*k-1), 3); \\ _Michel Marcus_, Nov 12 2014
%Y Cf. A028338, A161198.
%K nonn
%O 3,2
%A _Bill Gosper_
%E More terms from _Michel Marcus_, Nov 12 2014
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