A059262 Primes p such that x^9 = 2 has no solution mod p.

7, 13, 19, 37, 61, 67, 73, 79, 97, 103, 109, 139, 151, 163, 181, 193, 199, 211, 241, 271, 307, 313, 331, 337, 349, 367, 373, 379, 409, 421, 433, 463, 487, 523, 541, 547, 571, 577, 607, 613, 619, 631, 661, 673, 709, 739, 751, 757, 769, 787, 811, 823, 829, 853

Offset: 1

Author

Klaus Brockhaus, Jan 23 2001

Keywords

• easy
• nonn

Comments

Complement of A049596 relative to A000040.

Coincides for the first 207 terms with the sequence of primes p such that x^27 = 2 has no solution mod p (first divergence is at 3943, cf. A059354).

Links

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

Crossrefs

Cf. A000040, A049596, A059354.

Programs

Magma

[p: p in PrimesUpTo(900) | not exists{x: x in ResidueClassRing(p) | x^9 eq 2}]; // Vincenzo Librandi, Sep 20 2012

Mathematica

ok[p_] := Reduce[Mod[x^9 - 2, p] == 0, x, Integers] == False; Select[Prime[Range[150]], ok] (* Vincenzo Librandi, Sep 20 2012  *)