A040985 Primes p such that x^5 = 20 has no solution mod p.

11, 31, 41, 61, 101, 131, 151, 181, 191, 211, 241, 271, 281, 331, 431, 491, 521, 541, 571, 601, 631, 751, 761, 811, 821, 881, 911, 941, 971, 991, 1021, 1031, 1061, 1091, 1151, 1181, 1201, 1231, 1291, 1301, 1321, 1361, 1451, 1481

Offset

1,1

Comments

Complement of A216862 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^5 - 20, p] == 0, x, Integers] == False; Select[Prime[Range[300]], ok] (* Vincenzo Librandi, Sep 19 2012 *)

Prog

(Magma) [p: p in PrimesUpTo(1500) | not exists{x : x in ResidueClassRing(p) | x^5 eq 20} ]; // Vincenzo Librandi, Sep 19 2012

Crossrefs

Sequence in context: A089347 A287312 A240896 * A061599 A374028 A374029

Adjacent sequences: A040982 A040983 A040984 * A040986 A040987 A040988

Keyword

nonn,easy

Author

N. J. A. Sloane

Status

approved