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 A109076 Numbers n such that 11^n + 2 is prime. 10
 0, 1, 5, 9, 287, 8273, 121185 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS No further terms < 100000. - Ray Chandler, Jul 30 2011 a(8) > 2*10^5. - Robert Price, May 11 2014 LINKS EXAMPLE 11^5 + 2 = 161053 is prime, hence 5 is a term. MATHEMATICA Do[If[PrimeQ[11^n + 2], Print[n]], {n, 0, 5000}] PROG (PARI) is(n)=isprime(11^n+2) \\ Charles R Greathouse IV, Feb 17 2017 CROSSREFS Sequence in context: A002657 A046093 A097086 * A101683 A098135 A112259 Adjacent sequences:  A109073 A109074 A109075 * A109077 A109078 A109079 KEYWORD more,nonn AUTHOR Ryan Propper, Jun 17 2005 EXTENSIONS 8273 from Jason Earls (zevi_35711(AT)yahoo.com), Feb 29 2008 Edited by N. J. A. Sloane, Mar 02 2008 a(7) from Robert Price, May 11 2014 STATUS approved

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