OFFSET
1,2
COMMENTS
a(20) > 10^5 if it exists. - Michael S. Branicky, Aug 26 2024
MATHEMATICA
Select[Range[4000], PrimeQ[2^(# - 1) + 2# - 1] &] (* Alonso del Arte, Jul 09 2011 *)
PROG
(PARI) for(n=1, 10^6, if(ispseudoprime(2^(n-1)+2*n-1), print1(n, ", ")));
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Juri-Stepan Gerasimov, Jul 09 2011
EXTENSIONS
a(13)-a(19) from Michael S. Branicky, Jul 14 2023
STATUS
approved