A050834 Numbers k such that 165*2^k-1 is prime.

2, 3, 5, 6, 8, 11, 12, 15, 18, 23, 27, 36, 39, 44, 45, 56, 59, 63, 81, 84, 150, 188, 264, 275, 282, 299, 321, 338, 390, 552, 657, 722, 930, 1139, 1388, 1491, 1625, 2196, 2519, 2541, 2736, 2766, 3630, 4202, 4875, 5643, 6150, 10134, 20328, 20805, 22902, 25770, 30918

Offset

1,1

Links

Robert Price, Table of n, a(n) for n = 1..74

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[165*2^# - 1] & ] (* Robert Price, Dec 29 2018 *)

Prog

(PARI) is(n)=ispseudoprime(165*2^n-1) \\ Charles R Greathouse IV, Jun 13 2017

Crossrefs

Sequence in context: A005099 A161720 A105760 * A294911 A179799 A247588

Adjacent sequences: A050831 A050832 A050833 * A050835 A050836 A050837

Keyword

hard,nonn

Author

N. J. A. Sloane, Dec 29 1999

Extensions

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

a(54)-a(74) from the Wilfrid Keller link by Robert Price, Dec 29 2018

Status

approved