A032405 Numbers k such that 111*2^k+1 is prime.

1, 4, 28, 32, 44, 47, 71, 128, 137, 193, 676, 2344, 7828, 10883, 21596, 31724, 47783, 49816, 61300, 212396, 415412, 2382772, 2841992

Offset

1,2

Links

Table of n, a(n) for n=1..23.

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

Prog

(PARI) is(n)=ispseudoprime(111*2^n+1) \\ Charles R Greathouse IV, Jun 13 2017

Crossrefs

Sequence in context: A153431 A043074 A137314 * A344467 A307046 A179279

Adjacent sequences: A032402 A032403 A032404 * A032406 A032407 A032408

Keyword

nonn

Author

James R. Buddenhagen

Extensions

a(20)-a(21) from http://www.prothsearch.com/riesel1.html by Robert Price, Dec 14 2018

a(22)-a(23) from Jeppe Stig Nielsen, Jan 19 2020

Status

approved