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%I #34 Oct 25 2023 07:42:09
%S 1,12,120,1140,10626,98280,906192,8347680,76904685,708930508,
%T 6540715896,60403728840,558383307300,5166863427600,47855699958816,
%U 443643407165376,4116305022165108,38223742100828400,355214207837288800
%N a(n) = C(4n,n-2).
%D M. Abramowitz and I. A. Stegun, eds., Handbook of Mathematical Functions, National Bureau of Standards Applied Math. Series 55, 1964 (and various reprintings), p. 828.
%H Vincenzo Librandi, <a href="/A004332/b004332.txt">Table of n, a(n) for n = 2..200</a>
%H M. Abramowitz and I. A. Stegun, eds., <a href="http://www.convertit.com/Go/ConvertIt/Reference/AMS55.ASP">Handbook of Mathematical Functions</a>, National Bureau of Standards, Applied Math. Series 55, Tenth Printing, 1972 [alternative scanned copy].
%F G.f.: g*(g-1)^2/(4-3*g) where g = 1+x*g^4 is the g.f. of A002293. - _Mark van Hoeij_, Nov 17 2011
%F -3*(3*n+2)*(n-2)*(3*n+1)*a(n) + 8*(4*n-3)*(2*n-1)*(4*n-1)*a(n-1) = 0. - _R. J. Mathar_, May 27 2014
%t Table[Binomial[4n,n-2],{n,2,20}] (* _Harvey P. Dale_, Apr 11 2011 *)
%o (PARI) a(n) = binomial(4*n,n-2); \\ _Michel Marcus_, May 10 2020
%Y Cf. A002293.
%K nonn,easy
%O 2,2
%A _N. J. A. Sloane_
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