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A055698 Numbers n such that n | (sigma_4(n) + phi(n)^4). 0
1, 2, 6, 13588, 48238, 54490, 69004, 194460, 353228, 577980, 638652, 1478962, 1882188, 2190515, 2677740, 3404598, 3875508, 8456460, 9978863, 16320458, 41199780, 45112860, 76132715 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Sigma_4(n) is the sum of the 4th powers of the divisors of n (A001159).

LINKS

Table of n, a(n) for n=1..23.

MATHEMATICA

Do[If[Mod[DivisorSigma[4, n] + EulerPhi[n]^4, n]==0, Print[n]], {n, 1, 10^6}]

CROSSREFS

Sequence in context: A116899 A162146 A231545 * A121167 A115658 A005607

Adjacent sequences:  A055695 A055696 A055697 * A055699 A055700 A055701

KEYWORD

nonn

AUTHOR

Robert G. Wilson v, Jun 09 2000

EXTENSIONS

More terms from Robert G. Wilson v, Mar 11 2013

STATUS

approved

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Last modified July 21 19:25 EDT 2019. Contains 325199 sequences. (Running on oeis4.)