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A040126
Primes p such that x^4 = 13 has a solution mod p.
2
2, 3, 13, 17, 23, 43, 53, 61, 79, 103, 107, 127, 131, 139, 179, 181, 191, 199, 211, 251, 263, 283, 311, 337, 347, 367, 389, 419, 439, 443, 467, 491, 503, 523, 547, 563, 571, 599, 607, 641, 647, 659, 673, 677, 701
OFFSET
1,1
LINKS
MATHEMATICA
ok [p_]:=Reduce[Mod[x^4 - 13, p]== 0, x, Integers]=!= False; Select[Prime[Range[180]], ok] (* Vincenzo Librandi, Sep 12 2012 *)
PROG
(Magma) [p: p in PrimesUpTo(800) | exists(t){x : x in ResidueClassRing(p) | x^4 eq 13}]; // Vincenzo Librandi, Sep 12 2012
CROSSREFS
Sequence in context: A045341 A236950 A215322 * A215382 A144759 A215359
KEYWORD
nonn,easy
AUTHOR
STATUS
approved