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A272168
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a(n) = Product_{k=0..n} (k^2-k)!.
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2
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OFFSET
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0,3
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COMMENTS
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The next term has 114 digits.
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LINKS
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FORMULA
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a(n) ~ c * n^(n*(2*n^2 + 1)/3) * (2*Pi)^(n/2) / exp(5*n^3/9 + n/2 - Zeta(3) / (2*Pi^2)), where c = Product_{k>=2} (k*(k-1))!/stirling(k*(k-1)) = 1.086533635964823338078329042... and stirling(n) = sqrt(2*Pi*n) * n^n / exp(n) is the Stirling approximation of n!.
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MATHEMATICA
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Table[Product[(k^2-k)!, {k, 0, n}], {n, 0, 8}]
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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