A050836 Numbers n such that 169*2^n-1 is prime.

1, 5, 11, 17, 67, 137, 157, 203, 209, 227, 263, 917, 1039, 2581, 3659, 3691, 4337, 8249, 8927, 9749, 20807, 33439, 158003, 192323, 458099

Offset

1,2

Links

Table of n, a(n) for n=1..25.

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(169*2^n-1) \\ Charles R Greathouse IV, Jun 13 2017

Crossrefs

Sequence in context: A246704 A095183 A018730 * A058019 A182482 A075582

Adjacent sequences: A050833 A050834 A050835 * A050837 A050838 A050839

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