OFFSET
1,1
COMMENTS
10*1133^1133 - 9 is a probable prime.
a(6) > 3000. - Tyler NeSmith, May 15 2021
PROG
(PARI) isok(k) = ispseudoprime(10*k^k - 9); \\ Altug Alkan, Apr 02 2018
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Seiichi Manyama, Apr 02 2018
EXTENSIONS
a(6) from Michael S. Branicky, Mar 28 2023
STATUS
approved