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A040136
Primes p such that x^4 = 15 has no solution mod p.
2
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
OFFSET
1,1
COMMENTS
Complement of A040130 relative to A000040. - Vincenzo Librandi, Sep 18 2012
LINKS
MATHEMATICA
ok[p_]:= Reduce[Mod[x^4 - 15, p] == 0, x, Integers] == False; Select[Prime[Range[100]], ok] (* Vincenzo Librandi, Sep 18 2012 *)
PROG
(Magma) [p: p in PrimesUpTo(500) | not exists{x : x in ResidueClassRing(p) | x^4 eq 15} ]; // Vincenzo Librandi, Sep 18 2012
(PARI) is(n)=isprime(n) && !ispower(Mod(15, n), 4) \\ Charles R Greathouse IV, Feb 23 2017
CROSSREFS
Sequence in context: A334321 A034845 A241059 * A049482 A099651 A156666
KEYWORD
nonn,easy
AUTHOR
STATUS
approved