A216690 Primes p such that x^4 = -2 has no solution mod p.

5, 7, 13, 17, 23, 29, 31, 37, 41, 47, 53, 61, 71, 79, 97, 101, 103, 109, 127, 137, 149, 151, 157, 167, 173, 181, 191, 193, 197, 199, 223, 229, 239, 241, 263, 269, 271, 277, 293, 311, 313, 317, 349, 359, 367, 373, 383, 389, 397

Offset: 1

Author

Vincenzo Librandi, Sep 15 2012

Keywords

• nonn
• easy

Comments

Complement of A051071 relative to A000040.

Links

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

Crossrefs

Cf. A000040, A051071.

Programs

Mathematica

ok[p_]:= Reduce[Mod[x^4 + 2, p] == 0, x, Integers] == False; Select[Prime[Range[100]], ok]