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A055928
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Sum of square divisors of n! = sum of squares of divisors of the square root of largest square dividing n!.
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1
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1, 1, 1, 5, 5, 210, 210, 850, 7735, 806806, 806806, 3229590, 3229590, 161479500, 1455090000, 23286770000, 23286770000, 838446909300, 838446909300, 83973923013750, 83973923013750, 10244818607677500, 10244818607677500
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OFFSET
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1,4
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LINKS
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FORMULA
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MATHEMATICA
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f[p_, e_] := If[OddQ[e], (p^(e+1)-1)/(p^2-1) , (p^(e+2)-1)/(p^2-1)]; a[1] = 1; a[n_] := Times @@ (f @@@ FactorInteger[n!]); Array[a, 23] (* Amiram Eldar, Aug 01 2019 *)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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