A058765 Primes of the form 3^k - 2^k.

5, 19, 211, 129009091, 68629840493971, 617671248800299, 19383245658672820642055731, 14130386091162273752461387579, 1546132562196033990574082188840405015112916155251

Offset: 1

Author

N. J. A. Sloane, Jan 02 2001

Keywords

• nonn

Links

• Vincenzo Librandi, Table of n, a(n) for n = 1..12

Crossrefs

Cf. A001047 (3^n-2^n) and A057468 (k such that 3^k-2^k is prime).

Programs

GAP

Filtered(List([1..200],n->3^n - 2^n),IsPrime); # Muniru A Asiru, Mar 04 2018

Magma

[a: n in [0..300] | IsPrime(a) where a is  3^n - 2^n]; // Vincenzo Librandi, Dec 08 2011

Maple

select(isprime, [seq(3^n - 2^n, n=0..200)]); # Muniru A Asiru, Mar 04 2018

Mathematica

Select[Table[3^n-2^n, {n,0,2200}], PrimeQ] (* Vincenzo Librandi, Dec 08 2011 *)

PARI

lista(nn) = for(k=1, nn, if(isprime(p=3^k-2^k), print1(p", "))) \\ Altug Alkan, Mar 04 2018

Formula

a(n) = A001047(A057468(n)).