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A069166 Numbers n such that n*sum(d|n,1/sigma(d)) is an integer. 0
1, 6, 14, 40, 120, 244, 280, 440, 494, 680, 920, 1220, 2040, 2840, 2968, 3480, 6360, 9880, 10680, 16376, 20618, 25160, 32280, 34720, 40136, 40280, 42136, 45560, 45994, 46280, 85880, 91160, 120408 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..33.

MATHEMATICA

Select[Range[125000], IntegerQ[# Total[1/DivisorSigma[1, Divisors[#]]]]&] (* Harvey P. Dale, Nov 03 2017 *)

CROSSREFS

Sequence in context: A272579 A274896 A134259 * A184393 A281707 A093369

Adjacent sequences:  A069163 A069164 A069165 * A069167 A069168 A069169

KEYWORD

easy,nonn

AUTHOR

Benoit Cloitre, Apr 09 2002

STATUS

approved

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Last modified February 19 12:53 EST 2019. Contains 320310 sequences. (Running on oeis4.)