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A344731
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Numbers k such that k divides A306069(k).
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2
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1, 275, 277, 3337, 3353, 3359, 39675, 39689, 472467, 797806459, 9501109507
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OFFSET
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1,2
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COMMENTS
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The corresponding quotients A306069(k)/k are 1, 5, 5, 7, 7, 7, 9, 9, 11, 17, 19, ...
a(12) > 7.5*10^10, if it exists.
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LINKS
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EXAMPLE
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a(1) = 1 since A306069(1) = 1 is divisible by 1.
a(2) = 275 since A306069(275) = 1375 = 5 * 275 is divisible by 275.
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MATHEMATICA
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f[p_, e_] := If[Mod[e, 2] == 1, (e + 1), e]; s[1] = 1; s[n_] := s[n] = s[n - 1] + Times @@ f @@@ FactorInteger[n]; Select[Range[40000], Divisible[s[#], #] &]
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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STATUS
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approved
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