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A100407 Numbers n such that n^n+2 is prime. 6
1, 3, 737, 1349 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

All terms are odd. Next term is greater than 3500. 1349^1349+2 is a probable prime with length 4223.

The next term, if it exists, is greater than 50000. - Hugo Pfoertner, Jun 28 2019

LINKS

Table of n, a(n) for n=1..4.

EXAMPLE

737 is in the sequence because 737^737+2 is prime.

MATHEMATICA

Do[If[PrimeQ[n^n+2], Print[n]], {n, 3500}]

PROG

(PARI) is(n)=ispseudoprime(n^n+2) \\ Charles R Greathouse IV, May 22 2017

CROSSREFS

Cf. A100408.

Sequence in context: A013826 A255012 A133014 * A332173 A119264 A307926

Adjacent sequences:  A100404 A100405 A100406 * A100408 A100409 A100410

KEYWORD

more,nonn,hard

AUTHOR

Farideh Firoozbakht, Nov 19 2004

STATUS

approved

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Last modified February 24 22:04 EST 2020. Contains 332216 sequences. (Running on oeis4.)