OFFSET
1,1
MATHEMATICA
aQ[n_] := Length[Select[FactorInteger[n][[;; , 1]], # > 1 && PrimitiveRoot@# != 2 &]] == 0; Select[Range[2, 250], aQ] (* Amiram Eldar, Dec 09 2018 *)
PROG
(PARI) isokp(p) = znorder(Mod(2, p))==(p-1);
isok(n) = {if ((n>1) && (n % 2), my(f=factor(n)); #select(x->isokp(x), f[, 1]) == #f~; , 0); } \\ Michel Marcus, Dec 09 2018
CROSSREFS
KEYWORD
nonn
AUTHOR
Vladimir Shevelev, Jun 16 2008
EXTENSIONS
More terms from Michel Marcus, Dec 09 2018
STATUS
approved