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A216746
Primes p such that x^30 = -2 has no solution mod p.
2
5, 7, 11, 13, 19, 23, 29, 31, 37, 41, 47, 53, 61, 67, 71, 73, 79, 97, 101, 103, 109, 127, 131, 139, 149, 151, 157, 163, 167, 173, 181, 191, 193, 197, 199, 211, 223, 229, 239, 241, 263, 269, 271, 277, 281, 293, 311, 313, 317, 331, 337, 349, 359, 367, 373, 379, 383
OFFSET
1,1
COMMENTS
Complement of A051084 relative to A000040.
LINKS
MATHEMATICA
ok[p_]:=Reduce[Mod[x^30 + 2, p] == 0, x, Integers] == False; Select[Prime[Range[100]], ok]
PROG
(Magma) [ p: p in PrimesUpTo(400) | not exists{x : x in ResidueClassRing(p) | x^30 eq -2} ]; // Vincenzo Librandi, Sep 16 2012
CROSSREFS
Sequence in context: A298867 A039681 A375170 * A084441 A180950 A112397
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Sep 16 2012
STATUS
approved