OFFSET
1,2
LINKS
Ray Ballinger, Proth Search Page
Ray Ballinger and Wilfrid Keller, List of primes k.2^n + 1 for 300 < k < 600
Wilfrid Keller, List of primes k.2^n - 1 for k < 300
Eric Weisstein's World of Mathematics, Proth Prime
MAPLE
select(k->isprime(405*2^k+1), [$1..1000]); # Muniru A Asiru, Jan 04 2019
MATHEMATICA
Select[Range[1000], PrimeQ[405*2^# + 1] &]
CROSSREFS
KEYWORD
nonn,more,hard
AUTHOR
Robert Price, Jan 04 2019
EXTENSIONS
a(40) from Jeppe Stig Nielsen, May 30 2020
STATUS
approved