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A040105
Primes p such that x^4 = 5 has a solution mod p.
3
2, 5, 11, 19, 31, 59, 71, 79, 101, 109, 131, 139, 149, 151, 179, 181, 191, 199, 211, 239, 251, 269, 271, 311, 331, 359, 379, 389, 401, 409, 419, 431, 439, 449, 461, 479, 491, 499, 521, 541, 569, 571, 599, 619
OFFSET
1,1
LINKS
MATHEMATICA
ok [p_]:=Reduce[Mod[x^4- 5, p] == 0, x, Integers] =!= False; Select[Prime[Range[200]], ok] (* Vincenzo Librandi, Sep 11 2012 *)
PROG
(Magma) [p: p in PrimesUpTo(800) | exists(t){x : x in ResidueClassRing(p) | x^4 eq 5}]; // Vincenzo Librandi, Sep 11 2012
CROSSREFS
Sequence in context: A019341 A327265 A084572 * A319859 A156768 A134694
KEYWORD
nonn,easy
AUTHOR
STATUS
approved