A042969 Primes p such that x^7 = 3 has no solution mod p.

29, 43, 71, 113, 127, 197, 211, 239, 281, 337, 379, 421, 449, 463, 491, 547, 617, 631, 659, 673, 701, 743, 827, 911, 953, 967, 1009, 1051, 1093, 1163, 1303, 1373, 1429, 1471, 1499, 1667, 1709, 1723, 1933, 2003, 2017, 2087, 2129, 2143

Offset

1,1

Comments

Complement of A216881 relative to A000040. - Vincenzo Librandi, Sep 19 2012

Links

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

Mathematica

ok[p_]:= Reduce[Mod[x^7 - 3, p] == 0, x, Integers] == False; Select[Prime[Range[800]], ok] (* Vincenzo Librandi, Sep 19 2012  *)

Prog

(Magma) [p: p in PrimesUpTo(2500) | not exists{x : x in ResidueClassRing(p) | x^7 eq 3} ]; // Vincenzo Librandi, Sep 19 2012

Crossrefs

Sequence in context: A173967 A004619 A140444 * A042967 A061638 A136062

Adjacent sequences: A042966 A042967 A042968 * A042970 A042971 A042972

Keyword

nonn,easy

Author

N. J. A. Sloane

Status

approved