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A049555
Primes p such that x^23 = 2 has a solution mod p.
2
2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97, 101, 103, 107, 109, 113, 127, 131, 137, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199, 211, 223, 227, 229, 233, 239, 241, 251, 257, 263, 269, 271, 281, 283
OFFSET
1,1
COMMENTS
Complement of A040984 relative to A000040. - Vincenzo Librandi, Sep 14 2012
MATHEMATICA
ok[p_]:= Reduce[Mod[x^23 - 2, p] == 0, x, Integers] =!= False; Select[Prime[Range[150]], ok] (* Vincenzo Librandi, Sep 14 2012 *)
PROG
(Magma) [p: p in PrimesUpTo(300) | exists(t){x : x in ResidueClassRing(p) | x^23 eq 2}]; // Vincenzo Librandi, Sep 14 2012
CROSSREFS
Sequence in context: A103146 A329191 A154363 * A281295 A052042 A245576
KEYWORD
nonn,easy
STATUS
approved