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%I #7 Dec 07 2023 02:19:31
%S 1,5,2700,567567000,101370917007360000,26995322179162164731904000000,
%T 16635639072295355604762223305031680000000000,
%U 34026881962001914598329145027742925521204742717440000000000000
%N a(n) = Product_{i=1..n, j=1..n} (i + 4*j).
%F a(n) ~ A^(1/4) * 5^(25*n*(n+1)/8 + 29/48) * n^(n^2 - 29/48) / (Pi^(1/4) * Gamma(1/4)^(1/2) * 2^(n*(4*n+5) + 5/6) * exp(3*n^2/2 + 1/48)), where A = A074962 is the Glaisher-Kinkelin constant.
%t Table[Product[i + 4*j, {i, 1, n}, {j, 1, n}], {n, 0, 10}]
%Y Cf. A074962, A079478, A324402, A367956, A367958.
%K nonn
%O 0,2
%A _Vaclav Kotesovec_, Dec 06 2023