OFFSET
1,3
COMMENTS
Corresponding primes are 2, 2, 5, 11, 29, 53, 83, 239, 839, 628319, 1825823999, 51123071999, ...
EXAMPLE
4 is a term because 3*4!!! - 1 = 11 is prime.
PROG
(PARI) is(k) = ispseudoprime(3*prod(i=0, (k-2)\3, k-3*i) - 1); \\ Jinyuan Wang, Jun 09 2021
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Altug Alkan, Apr 06 2016
EXTENSIONS
a(46)-a(50) from Jinyuan Wang, Jun 09 2021
a(51) from Michael S. Branicky, Aug 09 2024
STATUS
approved