A050561 Numbers n such that 71*2^n-1 is prime.

2, 14, 410, 1390, 3770, 5434, 202642, 735802

Offset

1,1

Links

Table of n, a(n) for n=1..8.

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(71*2^n-1) \\ Charles R Greathouse IV, Jun 13 2017

Crossrefs

Sequence in context: A242876 A102596 A354465 * A346082 A135865 A337073

Adjacent sequences: A050558 A050559 A050560 * A050562 A050563 A050564

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