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A055709 Numbers n such that n | Sigma_5[n]. 5
1, 6, 22, 28, 66, 120, 198, 264, 308, 366, 440, 604, 672, 924, 984, 1320, 1464, 1694, 1717, 2013, 2296, 2464, 2574, 2970, 3434, 3608, 3960, 4026, 4228, 4598, 4920, 5082, 5151, 5348, 6200, 6600, 6644, 6776, 6868, 6888, 7320, 7392, 8052, 8128, 9504 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

sigma_5(n) is the sum of the 5th 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[5, n], n]==0, Print[n]], {n, 1, 15000}]

CROSSREFS

Sequence in context: A095411 A044448 A111036 * A037204 A035285 A069824

Adjacent sequences:  A055706 A055707 A055708 * A055710 A055711 A055712

KEYWORD

nonn

AUTHOR

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

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Last modified February 16 02:51 EST 2012. Contains 205860 sequences.