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A087886 Numbers n such that 29^n + 2 is prime. 8
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
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: A135444 A333041 A323726 * A123754 A048354 A046181
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 May 28 15:56 EDT 2024. Contains 372916 sequences. (Running on oeis4.)