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A353901
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Numbers k such that A353900(k) is divisible by k.
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0
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OFFSET
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1,2
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COMMENTS
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a(11) > 8*10^10, if it exists.
The corresponding ratios A353900(k)/k are 1, 2, 2, 1, 2, 1, 4, 2, 2, 1, ...
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LINKS
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EXAMPLE
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6 is a term since A353900(6) = 12 is divisible by 6.
56 is a term since A353900(56) = 56 is divisible by 56.
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MATHEMATICA
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f[p_, e_] := 1 + Sum[p^(2^k), {k, 0, Floor[Log2[e]]}]; s[1] = 1; s[n_] := Times @@ f @@@ FactorInteger[n]; Select[Range[6.5*10^6], 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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