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A040112
Primes p such that x^4 = 7 has a solution mod p.
2
2, 3, 7, 19, 29, 31, 37, 47, 59, 83, 103, 109, 113, 131, 139, 167, 193, 199, 223, 227, 251, 271, 283, 307, 311, 367, 383, 389, 419, 439, 449, 457, 467, 479, 503, 523, 563, 587, 607, 613, 619, 643, 647, 653, 691
OFFSET
1,1
LINKS
MATHEMATICA
ok [p_]:=Reduce[Mod[x^4- 7, 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 7}]; // Vincenzo Librandi, Sep 11 2012
CROSSREFS
Sequence in context: A349622 A078373 A038878 * A246373 A074855 A038935
KEYWORD
nonn,easy
AUTHOR
STATUS
approved