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A064030
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Product of unitary divisors of n!.
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1
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OFFSET
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1,2
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LINKS
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FORMULA
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EXAMPLE
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n = 6 has 8 unitary divisors:{16,45,9,80,5,144,1,720}, a(6) = 720^4 = 268738560000
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MATHEMATICA
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a[n_] := (n!)^(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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