A144487 Primes of the form 2^k + 15.

17, 19, 23, 31, 47, 79, 271, 1039, 2063, 4111, 32783, 65551, 4194319, 8388623, 67108879, 1073741839, 4294967311, 1099511627791, 4398046511119, 70368744177679, 2305843009213693967, 4722366482869645213711, 75557863725914323419151

Offset

1,1

Links

Vincenzo Librandi, Table of n, a(n) for n = 1..37

Formula

a(n) = 2^A057197(n) + 15. - Elmo R. Oliveira, Nov 08 2023

Mathematica

Select[2^Range[0, 200]+15, PrimeQ] (* Vladimir Joseph Stephan Orlovsky, Feb 03 2012 *)
Select[Table[2^n + 15, {n, 1, 300}], PrimeQ] (* Vincenzo Librandi, Feb 23 2014 *)

Prog

(PARI) {for(n=0, 72, if(isprime(k=2^n+15), print1(k, ", ")))}
(Magma)[a: n in [1..100] | IsPrime(a) where a is 2^n+15]; // Vincenzo Librandi, Feb 23 2014

Crossrefs

Cf. A000040, A057197 (numbers k such that 2^k + 15 is prime). [From Klaus Brockhaus, Dec 11 2008]

Sequence in context: A205700 A228070 A289685 * A108266 A102325 A231326

Adjacent sequences: A144484 A144485 A144486 * A144488 A144489 A144490

Keyword

nonn,easy

Author

Vincenzo Librandi, Dec 09 2008

Extensions

Edited by Klaus Brockhaus and R. J. Mathar, Dec 10 2008

Definition simplified by Jon E. Schoenfield, Jun 17 2010

Status

approved