OFFSET
1,3
COMMENTS
a(18) > 30000, if it exists. - Amiram Eldar, Dec 01 2021
MATHEMATICA
Select[Range[0, 2000], PrimeQ[2^(2#)-(2#-1)]&] Harvey P. Dale, May 20 2012
PROG
(PARI) for(x=0, 1000, if(isprime(2^(2*x)-(2*x-1)), print1(x, ", ")))
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Jorge Coveiro, Jul 25 2006
EXTENSIONS
a(14)-a(17) from Amiram Eldar, Dec 01 2021
a(18)-a(19) from Michael S. Branicky, May 15 2023
STATUS
approved