A040136 Primes p such that x^4 = 15 has no solution mod p.

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

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

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

Adjacent sequences: A040133 A040134 A040135 * A040137 A040138 A040139

Keyword

nonn,easy

Author

N. J. A. Sloane.

Status

approved