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A055703 Numbers n such that n | sigma_9(n) - phi(n)^9. 0
1, 2, 12, 54, 76, 90, 216, 423, 514, 531, 621, 2166, 2241, 2772, 2976, 4752, 5154, 5400, 5481, 6264, 7290, 7344, 9018, 9144, 9470, 9555, 14094, 14904, 19494, 21222, 23780, 25848, 28323, 34830, 34911, 38220, 40122, 48768, 49079, 55782, 59400 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

sigma_9(n) is the sum of the 9th powers of the divisors of n (A013957).

LINKS

Table of n, a(n) for n=1..41.

MATHEMATICA

Do[If[Mod[DivisorSigma[9, n]-EulerPhi[n]^9, n]==0, Print[n]], {n, 1, 10^5}]

PROG

(PARI) isok(n) = !((sigma(n, 9) - eulerphi(n)^9) % n); \\ Michel Marcus, Mar 02 2014

CROSSREFS

Sequence in context: A007225 A139046 A036359 * A242513 A006738 A212697

Adjacent sequences:  A055700 A055701 A055702 * A055704 A055705 A055706

KEYWORD

nonn

AUTHOR

Robert G. Wilson v, Jun 09 2000

EXTENSIONS

Definition corrected by Michel Marcus, Mar 02 2014

STATUS

approved

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Last modified November 14 04:56 EST 2019. Contains 329110 sequences. (Running on oeis4.)