A050833 Numbers k such that 163*2^k-1 is a prime.

3, 31, 63, 303, 4731, 31651, 45171, 96111, 105219, 341611, 577723

Offset

1,1

Links

Table of n, a(n) for n=1..11.

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 a prime

Mathematica

Select[Range[1000], PrimeQ[163*2^# - 1] & ] (* Robert Price, Dec 23 2018 *)

Crossrefs

Sequence in context: A341928 A238663 A141966 * A041207 A133203 A062616

Adjacent sequences: A050830 A050831 A050832 * A050834 A050835 A050836

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

Status

approved