OFFSET
1,1
COMMENTS
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..1000
MATHEMATICA
ok[p_]:= Reduce[Mod[x^56 + 2, p] == 0, x, Integers] =!= False; Select[Prime[Range[500]], ok] (* Vincenzo Librandi, Sep 16 2012 *)
PROG
(PARI) forprime(p=2, 2000, if([]~!=polrootsff(x^56+2, p, y-1), print1(p, ", "))); print();
/* or: */
forprime(p=2, 2000, if([]~!=polrootsmod(x^56+2, p), print1(p, ", "))); print(); /* faster */
/* Joerg Arndt, Jul 27 2011 */
(Magma) [p: p in PrimesUpTo(1600) | exists(t){x : x in ResidueClassRing(p) | x^56 eq - 2}]; // Vincenzo Librandi, Sep 16 2012
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
EXTENSIONS
More terms from Joerg Arndt, Jul 27 2011
STATUS
approved