OFFSET
1,1
LINKS
Jeppe Stig Nielsen, Table of n, a(n) for n = 1..47
Ray Ballinger and Wilfrid Keller, List of primes k.2^n + 1 for k < 300
Ray Ballinger, Proth Search Page
Wilfrid Keller, List of primes k.2^n - 1 for k < 300
PROG
(PARI) is(n)=ispseudoprime(27*2^n+1) \\ Charles R Greathouse IV, Jun 06 2017
CROSSREFS
KEYWORD
nonn,hard
AUTHOR
EXTENSIONS
More terms from Hugo Pfoertner, Jun 20 2003
More terms from Hugo Pfoertner, Aug 17 2004
Added more terms (from http://web.archive.org/web/20161028080239/http://www.prothsearch.net/riesel.html), Joerg Arndt, Apr 07 2013
STATUS
approved