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A049554
Primes p such that x^22 = 2 has a solution mod p.
2
2, 7, 17, 31, 41, 47, 71, 73, 79, 97, 103, 113, 127, 137, 151, 167, 191, 193, 223, 233, 239, 241, 257, 263, 271, 281, 311, 313, 337, 359, 367, 383, 401, 409, 431, 433, 439, 449, 457, 479, 487, 503, 521, 569, 577, 593, 599, 601, 607, 631, 641, 647, 673, 719
OFFSET
1,1
COMMENTS
Complement of A059311 relative to A000040. - Vincenzo Librandi, Sep 14 2012
MATHEMATICA
ok[p_]:= Reduce[Mod[x^22 - 2, p] == 0, x, Integers] =!= False; Select[Prime[Range[150]], ok] (* Vincenzo Librandi, Sep 14 2012 *)
PROG
(Magma) [p: p in PrimesUpTo(800) | exists(t){x : x in ResidueClassRing(p) | x^22 eq 2}]; // Vincenzo Librandi, Sep 14 2012
CROSSREFS
Sequence in context: A019357 A024920 A091313 * A019398 A086513 A166381
KEYWORD
nonn,easy
STATUS
approved