A267030 Primes p such that p*(3^p) + 2 is also prime.

3, 5, 11, 17, 317, 373, 10313

Offset: 1

Author

Emre APARI, Jan 09 2016

Keywords

• nonn
• more

Comments

The terms of this sequence are the prime terms of A265121.

The first few corresponding primes are 83, 1217, 1948619, 2195382773, ... .

a(8) > 10^5. - Michael S. Branicky, Oct 08 2024

Examples

			p = 17; [17 * (3 ^ 17) + 2] = 2195382773 (is a prime number).
		

Crossrefs

Cf. A265121.

Programs

Magma

[p: p in PrimesUpTo(1000) | IsPrime((p*(3^p)+2))]; // Vincenzo Librandi, Jan 10 2016

Maple

select(p -> isprime(p) and isprime(p*3^p+2), [seq(i,i=3..2000,2)]); # Robert Israel, Jan 10 2016

Mathematica

Select[Prime@ Range@ 1000, PrimeQ[# (3^#) + 2] &] (* Michael De Vlieger, Jan 09 2016 *)

PARI

lista(nn) = forprime(p=2, nn, if(ispseudoprime((p*(3^p) + 2)), print1(p, ", "))); \\ Altug Alkan, Jan 10 2016