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%I #21 Apr 02 2021 09:29:50
%S 1,252,19404,731808,16818516,267227532,3184461423,30107635272,
%T 235234907908,1566039386912,9095857138368,46960429261824,
%U 218772384397632,931020034054176,3656383418054268,13365232267026024,45800747571406905,148055097314224100
%N a(n) = Product_{i=1..n} ((i+5)*(i+6)*(i+7)*(i+8)*(i+9))/(i*(i+1)*(i+2)*(i+3)*(i+4)).
%C Number of tilings of a <5,n,5> hexagon.
%D O. D. Anderson, Find the next sequence, J. Rec. Math., 8 (No. 4, 1975-1976), 241.
%H Seiichi Manyama, <a href="/A047831/b047831.txt">Table of n, a(n) for n = 0..10000</a>
%H O. D. Anderson, <a href="/A002415/a002415.pdf">Find the next sequence</a>, J. Rec. Math., 8 (No. 4, 1975-1976), 241. [Annotated scanned copy]
%F a(n) = C(n+5,n+4)*C(n+6,n+3)*C(n+7,n+2)*C(n+8,n+1)*C(n+9,n)/(140*5!). - _Zerinvary Lajos_, May 29 2007
%p seq(binomial(n+5,n+4)*binomial(n+6,n+3)*binomial(n+7,n+2)*binomial(n+8,n+1)*binomial(n+9,n)/(140*5!), n=0..17); # _Zerinvary Lajos_, May 29 2007
%t Table[Product[Times@@(i+Range[5,9])/Times@@(i+Range[0,4]),{i,n}],{n,0,20}] (* _Harvey P. Dale_, Jan 30 2015 *)
%o (PARI) a(n) = prod(k=1, 5, binomial(n+k+4, n-k+5))/(140*5!); \\ _Seiichi Manyama_, Apr 02 2021
%Y Fifth row of array A103905.
%K nonn
%O 0,2
%A _N. J. A. Sloane_
%E Definition corrected by Daniel Soll (soll(AT)mathematik.uni-marburg.de), Aug 31 2004
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