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%I #7 Feb 03 2021 13:50:40
%S 1,2771340,44524428808860,835982760936614190900,
%T 16702642470437308383606668060,345116202503279265243707597937393840,
%U 7282855378270617096441349556073829143864900,155927544469969434644890704895476696960247603510200
%N a(n) = (20*n)!*n!/((10*n)!*(8*n)!*(3*n)!).
%F G.f.: hypergeom([1/20, 3/20, 7/20, 9/20, 11/20, 13/20, 17/20, 19/20], [1/8, 1/3, 3/8, 1/2, 5/8, 2/3, 7/8], 625000000/27*x).
%t Table[((20n)!n!)/((10n)!(8n)!(3n)!),{n,0,10}] (* _Harvey P. Dale_, Feb 03 2021 *)
%Y Cf. A295431.
%K nonn
%O 0,2
%A _Gheorghe Coserea_, Nov 28 2017