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A049562
Primes p such that x^30 = 2 has a solution mod p.
2
2, 17, 23, 47, 89, 113, 127, 137, 167, 223, 233, 239, 257, 263, 353, 359, 383, 431, 433, 439, 449, 457, 479, 503, 569, 593, 599, 617, 641, 647, 719, 727, 743, 809, 839, 857, 863, 887, 911, 919, 929, 953, 977, 983, 1049, 1097, 1103, 1193, 1217, 1223, 1289
OFFSET
1,1
COMMENTS
Complement of A059334 relative to A000040. - Vincenzo Librandi, Sep 14 2012
MATHEMATICA
ok[p_]:= Reduce[Mod[x^30 - 2, p] == 0, x, Integers] =!= False; Select[Prime[Range[300]], ok] (* Vincenzo Librandi, Sep 14 2012 *)
PROG
(Magma) [p: p in PrimesUpTo(1300) | exists(t){x : x in ResidueClassRing(p) | x^30 eq 2}]; // Vincenzo Librandi, Sep 14 2012
CROSSREFS
Sequence in context: A105901 A154963 A343241 * A107137 A086322 A340048
KEYWORD
nonn,easy
STATUS
approved