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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
OFFSET
1,1
COMMENTS
Complement of A040159 relative to A000040. - Vincenzo Librandi, Sep 18 2012
LINKS
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
KEYWORD
nonn,easy
AUTHOR
STATUS
approved