A050841 Numbers n such that 179*2^n-1 is prime.

8, 68, 108, 20780, 25488, 25656, 38684, 57096, 159108, 236856, 490800, 507816

Offset

1,1

Links

Table of n, a(n) for n=1..12.

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(179*2^n-1) \\ Charles R Greathouse IV, Jun 13 2017

Crossrefs

Sequence in context: A304073 A250258 A192091 * A208947 A296670 A263477

Adjacent sequences: A050838 A050839 A050840 * A050842 A050843 A050844

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