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A040136
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Primes p such that x^4 = 15 has no solution mod p.
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2
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13, 17, 19, 23, 29, 31, 37, 41, 47, 73, 79, 83, 89, 97, 101, 107, 139, 149, 151, 157, 167, 173, 193, 197, 199, 211, 227, 229, 233, 263, 269, 271, 277, 281, 293, 313, 331, 337, 347, 353, 373, 379, 383, 389, 397
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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^4 - 15, p] == 0, x, Integers] == False; Select[Prime[Range[100]], ok] (* Vincenzo Librandi, Sep 18 2012 *)
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PROG
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(Magma) [p: p in PrimesUpTo(500) | not exists{x : x in ResidueClassRing(p) | x^4 eq 15} ]; // Vincenzo Librandi, Sep 18 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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