1,2

Table of n, a(n) for n=1..39.

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

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

Select[Range[1000], PrimeQ[135*2^# - 1] & ] (* Robert Price, Dec 23 2018 *)

(PARI) is(n)=ispseudoprime(135*2^n-1) \\ Charles R Greathouse IV, Jun 13 2017

Sequence in context: A154766 A116594 A249723 * A189834 A248350 A247512

Adjacent sequences: A050590 A050591 A050592 * A050594 A050595 A050596

hard,nonn,more

N. J. A. Sloane, Dec 29 1999

a(27)-a(39) from the Wilfrid Keller link by Robert Price, Dec 23 2018

approved