

A050537


Numbers n such that 23*2^n1 is prime.


0



4, 6, 12, 46, 72, 244, 264, 544, 888, 1146, 14826, 24978, 103386, 323668, 458362, 496422
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

1,1


LINKS

Table of n, a(n) for n=1..16.
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^n1 (or k*2^n+1) is prime
Kosmaj, Riesel list k<300.


PROG

(PARI) is(n)=ispseudoprime(23*2^n1) \\ Charles R Greathouse IV, Jun 13 2017


CROSSREFS

Cf. A032361 23*2^n+1 is prime.
Sequence in context: A060202 A062624 A154666 * A114413 A068507 A133454
Adjacent sequences: A050534 A050535 A050536 * A050538 A050539 A050540


KEYWORD

hard,nonn


AUTHOR

N. J. A. Sloane, Dec 29 1999


EXTENSIONS

More terms from Hugo Pfoertner, Jul 14 2004
More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 02 2008


STATUS

approved



