A120329 - OEIS

A120329

Nonprime integers n such that n divides A120492(n).

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