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A040160 Primes p such that x^5 = 2 has no solution mod p. 4
11, 31, 41, 61, 71, 101, 131, 181, 191, 211, 271, 281, 311, 331, 401, 421, 461, 491, 521, 541, 601, 631, 661, 691, 701, 751, 761, 811, 821, 881, 941, 991, 1021, 1031, 1051, 1061, 1091, 1151, 1171, 1201, 1231, 1291, 1301, 1321, 1361, 1381, 1451, 1471, 1481, 1511, 1531, 1571 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Complement of A040159 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^5 - 2, p] == 0, x, Integers] == False; Select[Prime[Range[300]], ok] (* Vincenzo Librandi, Sep 18 2012  *)

PROG

(MAGMA) [p: p in PrimesUpTo(1300) | forall{x: x in ResidueClassRing(p) | x^5 ne 2}]; // Bruno Berselli, Sep 12 2012

(MAGMA) [p: p in PrimesUpTo(1500) | not exists{x : x in ResidueClassRing(p) | x^5 eq 2} ]; // Vincenzo Librandi, Sep 18 2012

(PARI) forprime(p=2, 10^3, if(#polrootsmod(x^5-2, p)==0, print1(p, ", "))) \\ Joerg Arndt, Jul 16 2015

CROSSREFS

Sequence in context: A040975 A188384 A040172 * A040981 A181603 A040983

Adjacent sequences:  A040157 A040158 A040159 * A040161 A040162 A040163

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane.

STATUS

approved

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Last modified December 8 02:07 EST 2016. Contains 278902 sequences.