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A055711
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Numbers n such that n | Sigma_7[n].
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0
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1, 6, 28, 86, 120, 145, 258, 290, 435, 496, 580, 588, 672, 696, 870, 946, 1032, 1305, 1720, 1740, 2245, 2610, 2712, 2838, 3164, 3282, 3408, 3480, 3724, 3784, 4060, 4490, 5160, 5220, 6735, 6786, 6960, 7830, 8514, 8980, 9436, 9492, 9632, 9976
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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COMMENTS
| sigma_7(n) is the sum of the 7th powers of the divisors of n.
Problem 11090 proves that this sequence is infinite. - T. D. Noe (noe(AT)sspectra.com), Apr 18 2006
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REFERENCES
| Florian Luca, Problem 11090: Sometimes n divides sigma_k(n), Amer. Math. Monthly 113 (2006), 372-373.
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MATHEMATICA
| Do[If[Mod[DivisorSigma[7, n], n]==0, Print[n]], {n, 1, 10000}]
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CROSSREFS
| Sequence in context: A119174 A144945 A202956 * A141255 A091321 A125310
Adjacent sequences: A055708 A055709 A055710 * A055712 A055713 A055714
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KEYWORD
| nonn
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AUTHOR
| Robert G. Wilson v (rgwv(AT)rgwv.com), Jun 09 2000
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