A102870 Primes of the form 3^n+8.

11, 17, 89, 251, 6569, 1594331, 4782977, 3486784409, 1350851717672992097, 984770902183611232889, 5474401089420219382077155933569751771, 969773729787523602876821942164080815560169

Offset

1,1

Comments

The sequence of corresponding n starts 1, 2, 4, 5, 8, 13, 14, 20, 38, 44, 77, 88, 124, 152, 244, 557,... (complete up to 10^3). [Joerg Arndt, Jul 19 2012]

Links

Vincenzo Librandi, Table of n, a(n) for n = 1..16

Formula

a(m) = if[ 3^n+8 is prime then a[m]=3^n+8, for n=1 to 200]

Mathematica

a = Delete[Union[Flatten[Table[If [PrimeQ[3^n + 8] == True, 3^n + 8, 0], {n, 1, 200}]]], 1]
Select[Table[3^n+8, {n, 0, 200}], PrimeQ] (* Vincenzo Librandi, Jul 19 2012 *)

Prog

(Magma) [ a: n in [0..100] | IsPrime(a) where a is 3^n+8 ]; // Vincenzo Librandi, Jul 19 2012

Crossrefs

Sequence in context: A324795 A250716 A244853 * A136721 A107172 A090286

Adjacent sequences: A102867 A102868 A102869 * A102871 A102872 A102873

Keyword

nonn

Author

Roger L. Bagula, Mar 01 2005

Status

approved