OFFSET
1,1
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..1000
MATHEMATICA
ok[p_]:= Reduce[Mod[x^19 - 2, p] == 0, x, Integers] == False; Select[Prime[Range[4000]], ok] (* Vincenzo Librandi, Sep 20 2012 *)
PROG
(Magma) [p: p in PrimesUpTo(7500) | not exists{x : x in ResidueClassRing(p) | x^19 eq 2} ]; // Vincenzo Librandi, Sep 20 2012
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Klaus Brockhaus, Jan 21 2001
STATUS
approved