A050568 Numbers n such that 85*2^n-1 is prime.

5, 11, 71, 113, 115, 355, 473, 563, 883, 1235, 5735, 9809, 11311, 14491, 25495, 125675, 128459, 147115, 656039, 683573, 1034069

Offset

1,1

Links

Table of n, a(n) for n=1..21.

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

Kosmaj, Riesel list k<300.

Prog

(PARI) is(n)=ispseudoprime(85*2^n-1) \\ Charles R Greathouse IV, Jun 13 2017

Crossrefs

Sequence in context: A239322 A101209 A216071 * A065555 A189802 A328453

Adjacent sequences: A050565 A050566 A050567 * A050569 A050570 A050571

Keyword

hard,nonn

Author

N. J. A. Sloane, Dec 29 1999

Extensions

More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 02 2008

Status

approved