A050558 Numbers n such that 65*2^n-1 is prime.

4, 6, 12, 22, 28, 52, 78, 94, 124, 162, 174, 192, 204, 304, 376, 808, 930, 972, 1714, 1776, 2176, 2568, 4392, 4728, 5548, 8046, 12474, 26856, 27156, 45240, 52026, 134598, 179658, 185946, 578512, 647130

Offset

1,1

Links

Table of n, a(n) for n=1..36.

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(65*2^n-1) \\ Charles R Greathouse IV, Jun 13 2017

Crossrefs

Sequence in context: A049478 A263458 A163776 * A331192 A255843 A098145

Adjacent sequences: A050555 A050556 A050557 * A050559 A050560 A050561

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