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A040087
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Primes p such that x^3 = 21 has a solution mod p.
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2
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2, 3, 5, 7, 11, 13, 17, 23, 29, 41, 43, 47, 53, 59, 71, 73, 79, 83, 89, 101, 107, 113, 131, 137, 149, 163, 167, 173, 179, 191, 197, 227, 229, 233, 239, 241, 251, 257, 263, 269, 277, 281, 283, 293, 311, 317, 347, 349
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OFFSET
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1,1
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COMMENTS
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LINKS
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MATHEMATICA
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ok[p_]:=Reduce[Mod[x^3 - 21, p] == 0, x, Integers] =!= False; Select[Prime[Range[180]], ok] (* Vincenzo Librandi, Sep 11 2012 *)
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PROG
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(Magma) [p: p in PrimesUpTo(450) | exists(t){x : x in ResidueClassRing(p) | x^3 eq 21}]; // Vincenzo Librandi, Sep 11 2012
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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