A076513 Numbers n such that 2+2^n+3^n is prime.

1, 3, 5, 65, 119, 213, 1209, 2469, 2669, 3939, 11219

Offset

1,2

Comments

119, 213, 1209 and 2469 proved prime by Primo v1.2.1. - Robert G. Wilson v Oct 17 2002

a(12) > 10^5. - Giovanni Resta, Mar 19 2014

Links

Table of n, a(n) for n=1..11.

Mathematica

Do[ If[ PrimeQ[2 + 2^n + 3^n], Print[n]], {n, 1, 4000, 2}]
Select[Range[10000], PrimeQ[2 + 2^# + 3^#] &] (* _Vincenzo Librandi: Oct 05 2012 *)

Prog

(PARI) is(n)=ispseudoprime(2+2^n+3^n) \\ Charles R Greathouse IV, Jun 13 2017

Crossrefs

Cf. A075996.

Sequence in context: A181904 A319584 A318546 * A222611 A261071 A247862

Adjacent sequences: A076510 A076511 A076512 * A076514 A076515 A076516

Keyword

nonn,more

Author

Zak Seidov, Oct 17 2002

Extensions

Edited and extended by Robert G. Wilson v, Oct 17 2002

a(10) from Vincenzo Librandi, Oct 05 2012

a(11) from Giovanni Resta, Feb 19 2013

Status

approved