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A055713 Numbers n such that n | Sigma_9[n]. 0
1, 6, 38, 42, 54, 114, 120, 135, 168, 190, 216, 222, 266, 270, 280, 285, 312, 342, 378, 456, 496, 540, 570, 672, 728, 760, 798, 840, 888, 945, 1026, 1064, 1080, 1140, 1330, 1512, 1554, 1560, 1710, 1782, 1806, 1862, 1890, 1962, 1976, 1995, 1998, 2160, 2166 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

sigma_9(n) is the sum of the 9th powers of the divisors of n.

Problem 11090 proves that this sequence is infinite. - T. D. Noe (noe(AT)sspectra.com), Apr 18 2006

REFERENCES

Florian Luca, Problem 11090: Sometimes n divides sigma_k(n), Amer. Math. Monthly 113 (2006), 372-373.

MATHEMATICA

Do[If[Mod[DivisorSigma[9, n], n]==0, Print[n]], {n, 1, 5000}]

CROSSREFS

Sequence in context: A083373 A015492 A039293 * A060454 A060452 A045949

Adjacent sequences:  A055710 A055711 A055712 * A055714 A055715 A055716

KEYWORD

nonn

AUTHOR

Robert G. Wilson v (rgwv(AT)rgwv.com), Jun 09 2000

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Last modified February 16 13:12 EST 2012. Contains 205909 sequences.