A176922 Primes of the form 2^k + 23.

31, 151, 549755813911, 604462909807314587353111

Offset: 1

Author

Vincenzo Librandi, Apr 29 2010

Keywords

• nonn

Links

• Vincenzo Librandi, Table of n, a(n) for n = 1..8

Crossrefs

Cf. A000040, A057203.

Programs

Magma

[a: n in [0..750] | IsPrime(a) where a is 2^n+23];

Mathematica

Select[Table[2^n + 23, {n, 0, 750}], PrimeQ] (* Vincenzo Librandi Jan 02 2014 *)

Formula

a(n) = 2^A057203(n) + 23. [R. J. Mathar, Jun 18 2010]