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A055705
Numbers n such that n | Sigma_11(n) - Phi(n)^11.
0
1, 2, 10, 12, 82, 168, 952, 1716, 2732, 2970, 5627, 8185, 11400, 12871, 20104, 20368, 23526, 25749, 70176, 82920, 111194, 117151, 119160, 128790, 134670, 143136, 185140, 193020, 208352, 240408, 247995, 251856, 291368, 354588, 565768, 592006, 642600, 783315
OFFSET
1,2
COMMENTS
sigma_11(n) is the sum of the 11th powers of the divisors of n (A013959).
MATHEMATICA
Do[If[Mod[DivisorSigma[11, n]-EulerPhi[n]^11, n]==0, Print[n]], {n, 10^5}]
Select[Range[800000], Divisible[DivisorSigma[11, #]-EulerPhi[#]^11, #]&] (* Harvey P. Dale, Apr 15 2018 *)
PROG
(PARI) isok(n) = !((sigma(n, 11) - eulerphi(n)^11) % n); \\ Michel Marcus, Mar 02 2014
CROSSREFS
Cf. A000010.
Sequence in context: A209445 A181427 A055697 * A156430 A347336 A303356
KEYWORD
nonn
AUTHOR
Robert G. Wilson v, Jun 09 2000
EXTENSIONS
Definition corrected and more terms from Michel Marcus, Mar 02 2014
STATUS
approved