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A346010
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a(n) is the denominator of the average number of distinct prime factors of the divisors of n.
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9
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1, 2, 2, 3, 2, 1, 2, 4, 3, 1, 2, 6, 2, 1, 1, 5, 2, 6, 2, 6, 1, 1, 2, 4, 3, 1, 4, 6, 2, 2, 2, 6, 1, 1, 1, 3, 2, 1, 1, 4, 2, 2, 2, 6, 6, 1, 2, 10, 3, 6, 1, 6, 2, 4, 1, 4, 1, 1, 2, 3, 2, 1, 6, 7, 1, 2, 2, 6, 1, 2, 2, 12, 2, 1, 6, 6, 1, 2, 2, 10, 5, 1, 2, 3, 1, 1
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OFFSET
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1,2
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COMMENTS
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LINKS
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MATHEMATICA
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a[n_] := Denominator[DivisorSum[n, PrimeNu[#] &]/DivisorSigma[0, n]]; Array[a, 100]
(* or *)
f[p_, e_] := e/(e+1); a[1] = 1; a[n_] := Denominator[Plus @@ f @@@ FactorInteger[n]]; Array[a, 100]
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CROSSREFS
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KEYWORD
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nonn,frac
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AUTHOR
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STATUS
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approved
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