A050580 Numbers n such that 109*2^n-1 is prime.

9, 149, 177, 419, 617, 1799, 3227, 6017, 12957, 141227

Offset

1,1

Links

Table of n, a(n) for n=1..10.

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(109*2^n-1) \\ Charles R Greathouse IV, Jun 13 2017

Crossrefs

Sequence in context: A006691 A304312 A361066 * A266128 A183439 A296017

Adjacent sequences: A050577 A050578 A050579 * A050581 A050582 A050583

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