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A055697 Numbers n such that n | Sigma_3(n) + Phi(n)^3. 0
1, 2, 10, 12, 78, 198, 1278, 1470, 1491, 2376, 2472, 6768, 7659, 7774, 9858, 10912, 11904, 12862, 16660, 25758, 35586, 38976, 39102, 40986, 41144, 44688, 59520, 72961, 80304, 84084, 94365 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

sigma_3(n) is the sum of the cubes of the divisors of n (A001158).

LINKS

Table of n, a(n) for n=1..31.

MATHEMATICA

Do[If[Mod[DivisorSigma[3, n]+EulerPhi[n]^3, n]==0, Print[n]], {n, 1, 2*10^5}]

CROSSREFS

Sequence in context: A106455 A209445 A181427 * A055705 A156430 A303356

Adjacent sequences:  A055694 A055695 A055696 * A055698 A055699 A055700

KEYWORD

nonn

AUTHOR

Robert G. Wilson v, Jun 09 2000

STATUS

approved

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Last modified August 23 22:45 EDT 2019. Contains 326254 sequences. (Running on oeis4.)