A050832 Numbers k such that 161*2^k-1 is prime.

2, 6, 18, 22, 34, 54, 98, 122, 146, 222, 306, 422, 654, 682, 862, 1010, 1346, 1582, 7890, 9714, 12498, 21742, 27810, 34798, 74382, 97746, 205370, 249710, 371426, 394974, 447330, 587570

Offset

1,1

Links

Table of n, a(n) for n=1..32.

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[161*2^# - 1] & ] (* Robert Price, Dec 23 2018 *)

Prog

(PARI) is(n)=ispseudoprime(161*2^n-1) \\ Charles R Greathouse IV, Jun 13 2017

Crossrefs

Sequence in context: A151870 A045962 A127257 * A300600 A342035 A168149

Adjacent sequences: A050829 A050830 A050831 * A050833 A050834 A050835

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(32) from the Wilfrid Keller link by Robert Price, Dec 23 2018

Status

approved