A274022 Primes of the form 2^(2^k) + 3.

5, 7, 19, 65539

Offset: 1

Author

Vincenzo Librandi, Jun 07 2016

Keywords

• nonn

Comments

Terms given correspond to n = 0, 1, 2, and 4.

Next term >= 2^2^28 + 3. - Charles R Greathouse IV, Jun 08 2016

Crossrefs

Cf. A019434, A130730.

Cf. similar sequences listed in A273547.

Programs

Magma

[a: n in [0..10] | IsPrime(a) where a is 2^(2^n)+3];

Mathematica

Select[Table[2^(2^n) + 3, {n, 0, 15}], PrimeQ]

PARI

for(n=0,4, if(ispseudoprime(t=2^2^n+3), print1(t", "))) \\ Charles R Greathouse IV, Jun 08 2016