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A120329 Nonprime integers n such that n divides A120492(n). 3
1, 4, 6, 9, 10, 12, 22, 45, 400, 417, 561, 620, 1045, 1105, 1146, 1729, 1897, 2465, 2821, 3745, 3825, 4071, 4961, 5365, 5785, 6187, 6601, 6994, 8911, 10143, 10413, 10585, 10609, 12189, 15841, 15905, 18705, 28692, 29341, 32757, 39831, 41041, 46657 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

A120492(n) = 1 + Sum_{k=1..n} Prime(k)^(n-1).

Pi(A120329)<=10^n: 1, 5, 8, 12, 29, 55, ..., . - Robert G. Wilson v, Aug 20 2006

LINKS

Table of n, a(n) for n=1..43.

MATHEMATICA

fQ[n_] := IntegerQ[(1 + Sum[ PowerMod[ Prime[k], n - 1, n], {k, n}])/n]; Do[ If[ !PrimeQ@n && fQ@n, Print@n], {n, 52632}] (* Robert G. Wilson v *)

CROSSREFS

Cf. A120492, A121166: Integers n such that n divides A120492(n).

Sequence in context: A175127 A174166 A171401 * A182800 A123249 A171136

Adjacent sequences:  A120326 A120327 A120328 * A120330 A120331 A120332

KEYWORD

nonn

AUTHOR

Alexander Adamchuk, Aug 16 2006

EXTENSIONS

Edited and extended, a(13) - a(43), by Robert G. Wilson v, Aug 20 2006

STATUS

approved

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Last modified October 15 13:38 EDT 2019. Contains 328030 sequences. (Running on oeis4.)