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A064031
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Product of non-unitary divisors of n!.
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1
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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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EXAMPLE
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n=6: 720 has 22 non-unitary divisors: a(6)=720^11=26956124946896309452800000000000
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MATHEMATICA
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a[n_] := (n!)^(DivisorSigma[0, n!]/2 - 2^(PrimePi[n]-1)); Array[a, 10] (* Amiram Eldar, Jul 16 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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