OFFSET
1,1
COMMENTS
9584444 is also a term (cf. PrimeGrid, 2020). - Felix Fröhlich, Dec 10 2020
LINKS
Ray Ballinger, Proth Search Page
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
PrimeGrid, Announcement of 9584444, 2020.
MATHEMATICA
Select[Range[1000], PrimeQ[121*2^# + 1] & ] (* Robert Price, Dec 17 2018 *)
PROG
(PARI) is(n)=ispseudoprime(121*2^n+1) \\ Charles R Greathouse IV, Jun 13 2017
CROSSREFS
KEYWORD
nonn,hard,more
AUTHOR
EXTENSIONS
Extended by Hugo Pfoertner, Jul 02 2003
a(20)-a(24) from the Ray Ballinger and Wilfrid Keller link by Robert Price, Dec 17 2018
STATUS
approved