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A087886 Numbers n such that 29^n + 2 is prime. 7
0, 1, 3, 63, 87, 189, 239, 605, 2099, 3667, 5029, 20025, 45285, 99167 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

After 0, all terms are odd. [Bruno Berselli, Oct 02 2014]

LINKS

Table of n, a(n) for n=1..14.

Henri & Renaud Lifchitz, PRP Records.

EXAMPLE

a(1) = 1 is a member because 29^1 + 2 = 31 is prime.

29^3+2 = 24391 is prime, so 3 is in the sequence.

PROG

(PARI) for( n = 0, 239, if( isprime( 29^n +2), print( n), ))

CROSSREFS

Cf. A051783, n such that 3^n +2 is prime.

Cf. A087885, 5^n +2 is prime.

Sequence in context: A144422 A135444 A182468 * A123754 A048354 A046181

Adjacent sequences:  A087883 A087884 A087885 * A087887 A087888 A087889

KEYWORD

nonn,more

AUTHOR

Donald S. McDonald, Oct 13 2003

EXTENSIONS

a(8) from Mark Hudson (mrmarkhudson(AT)hotmail.com), Sep 07 2004

a(9) - a(11), corresponding to probable primes, from Ryan Propper, Jul 03 2005

Edited by T. D. Noe, Oct 30 2008

a(12) from Ray Chandler, Aug 01 2011

a(13) from Ray Chandler, Aug 02 2011

a(14) from Ray Chandler, Aug 08 2011

STATUS

approved

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Last modified January 18 13:01 EST 2019. Contains 319271 sequences. (Running on oeis4.)