A055704 - OEIS

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A055704

Numbers k such that n | sigma_10(k) + phi(k)^10.

1, 2, 6, 38, 551, 589, 750, 2510, 3277, 7801, 9940, 11359, 16810, 19875, 21250, 23700, 30450, 33000, 34350, 41005, 117670, 132300, 144300, 145150, 161700, 234635, 242550, 249000, 308700, 365750, 407925, 423801, 437250, 468150, 524700, 577850, 585206, 616585

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

COMMENTS

sigma_10(k) is the sum of the 10th powers of the divisors of k (A013958).

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..170

MATHEMATICA

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

PROG

(PARI) isok(n) = !((sigma(n, 10) + eulerphi(n)^10) % n); \\ Michel Marcus, Mar 02 2014

CROSSREFS