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 A325053 a(n) = Product_{i=0..n, j=0..n} (i! + j! + 1). 1

%I

%S 3,81,103680,447180963840,7014935716261432173527040,

%T 1921470539412808834455592518302690305036517376000,

%U 81601182941928855942156180258180656419177691149082352022004942698629910149621350400000

%N a(n) = Product_{i=0..n, j=0..n} (i! + j! + 1).

%F a(n) = A306729(n) * Product_{i=0..n, j=0..n} (1 + 1/(i! + j!)).

%F a(n) ~ c * A324569 * 2^(n^2/2 + 2*n) * Pi^(n^2/2 + n) * n^(2*n^3/3 + 2*n^2 + 11*n/6 + 5/2) / exp(8*n^3/9 + 2*n^2 + n), where c = Product_{i>=0, j>=0} (1 + 1/(i! + j!)) = 71.32069635593350979104242285703294604508330622582076432053456223608...

%t Table[Product[i! + j! + 1, {i, 0, n}, {j, 0, n}], {n, 0, 7}]

%Y Cf. A107254, A306729, A325052.

%K nonn

%O 0,1

%A _Vaclav Kotesovec_, Mar 26 2019

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Last modified May 27 10:32 EDT 2022. Contains 354096 sequences. (Running on oeis4.)