A050582 Numbers k such that 113*2^k-1 is prime.

8, 14, 74, 80, 274, 334, 590, 608, 614, 650, 1016, 1814, 1904, 4400, 5474, 144866, 174898, 343214, 422866, 464386, 572966, 1389674, 1425998

Offset

1,1

Links

Table of n, a(n) for n=1..23.

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

Kosmaj, Riesel list k<300.

Index entries for sequences of n such that k*2^n-1 (or k*2^n+1) is prime

Mathematica

Select[Range[1000], PrimeQ[113*2^# - 1] & ] (* Robert Price, Dec 23 2018 *)

Prog

(PARI) is(n)=ispseudoprime(113*2^n-1) \\ Charles R Greathouse IV, Jun 13 2017

Crossrefs

Sequence in context: A218555 A268160 A236553 * A128451 A177170 A275006

Adjacent sequences: A050579 A050580 A050581 * A050583 A050584 A050585

Keyword

hard,nonn,more

Author

N. J. A. Sloane, Dec 29 1999

Extensions

More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 02 2008

a(21)-a(23) from the Wilfrid Keller link by Robert Price, Dec 23 2018

Status

approved