A032409 Numbers k such that 119*2^k + 1 is prime.

1, 3, 7, 13, 21, 23, 45, 63, 553, 1115, 2471, 2773, 7363, 25767, 26265, 32445, 41291, 55583, 113637, 376951, 787017, 858427, 915371, 1242207, 1759247, 3161195

Offset

1,2

Links

Table of n, a(n) for n=1..26.

Ray Ballinger, Proth Search Page

Ray Ballinger and Wilfrid Keller, List of primes k.2^n + 1 for k < 300

Y. Gallot, Proth.exe: Windows Program for Finding Large Primes

Wilfrid Keller, List of primes k.2^n - 1 for k < 300

Index entries for sequences of n such that k*2^n-1 (or k*2^n+1) is prime

Mathematica

Select[Range[1000], PrimeQ[119*2^# + 1] & ] (* Robert Price, Dec 17 2018 *)

Prog

(PARI) is(n)=ispseudoprime(119*2^n+1) \\ Charles R Greathouse IV, Jun 13 2017

Crossrefs

Sequence in context: A169633 A069194 A100531 * A073896 A299478 A355310

Adjacent sequences: A032406 A032407 A032408 * A032410 A032411 A032412

Keyword

nonn,more

Author

James R. Buddenhagen

Extensions

Extended by Hugo Pfoertner, Jul 02 2003

a(20)-a(25) from the Ray Ballinger and Wilfrid Keller link by Robert Price, Dec 17 2018

a(26) from Jeppe Stig Nielsen, Jan 15 2022

Status

approved