OFFSET
1,1
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..660
MATHEMATICA
Select[ Prime@Range@221000, PrimitiveRoot@# == 39 &] (* Robert G. Wilson v, May 11 2001 *)
PROG
(PARI) is(n)=if(n<9||!isprime(n), return(0)); for(k=2, 38, if(znorder(Mod(k, n))==n-1, return(0))); znorder(Mod(39, n))==n-1 \\ Charles R Greathouse IV, Apr 28 2015
CROSSREFS
KEYWORD
nonn
AUTHOR
Klaus Brockhaus, May 06 2001
EXTENSIONS
More terms from Robert G. Wilson v, May 11 2001 and Dec 21 2005
STATUS
approved