A109076 Numbers n such that 11^n + 2 is prime.

0, 1, 5, 9, 287, 8273, 121185, 303909

Offset: 1

Author

Ryan Propper, Jun 17 2005

Keywords

• more
• nonn

Comments

No further terms < 100000. - Ray Chandler, Jul 30 2011

a(8) > 2*10^5. - Robert Price, May 11 2014

Examples

			11^5 + 2 = 161053 is prime, hence 5 is a term.
		

Programs

Mathematica

Do[If[PrimeQ[11^n + 2], Print[n]], {n, 0, 5000}]

PARI

is(n)=isprime(11^n+2) \\ Charles R Greathouse IV, Feb 17 2017

Extensions

8273 from Jason Earls, Feb 29 2008

Edited by N. J. A. Sloane, Mar 02 2008

a(7) from Robert Price, May 11 2014

a(8) from Paul Bourdelais, Aug 02 2023