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A042973
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Primes p such that x^7 = 5 has no solution mod p.
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2
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29, 43, 113, 127, 197, 211, 239, 281, 337, 379, 421, 449, 463, 491, 547, 617, 631, 659, 673, 701, 743, 757, 911, 953, 967, 1009, 1051, 1093, 1163, 1289, 1373, 1429, 1471, 1499, 1583, 1597, 1667, 1709, 1723, 1877, 1933, 2003, 2017, 2087
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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^7 - 5, p] == 0, x, Integers] == False; Select[Prime[Range[800]], ok] (* Vincenzo Librandi, Sep 19 2012 *)
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PROG
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(Magma) [p: p in PrimesUpTo(2500) | not exists{x : x in ResidueClassRing(p) | x^7 eq 5} ]; // Vincenzo Librandi, Sep 19 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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