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A040171 Primes p such that x^5 = 7 has a solution mod p. 2
2, 3, 5, 7, 13, 17, 19, 23, 29, 37, 43, 47, 53, 59, 67, 73, 79, 83, 89, 97, 103, 107, 109, 113, 127, 137, 139, 149, 157, 163, 167, 173, 179, 181, 193, 197, 199, 223, 227, 229, 233, 239, 257, 263, 269, 277, 283, 293 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Complement of A040172 relative to A000040. - Vincenzo Librandi, Sep 13 2012

LINKS

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

MATHEMATICA

ok [p_]:= Reduce[Mod[x^5 - 7, p] == 0, x, Integers] =!= False; Select[Prime[Range[150]], ok] (* Vincenzo Librandi, Sep 12 2012 *)

PROG

(MAGMA) [p: p in PrimesUpTo(300) | exists{x: x in ResidueClassRing(p) | x^5 eq 7}]; // Vincenzo Librandi, Sep 12 2012

CROSSREFS

Cf. A000040, A040172.

Sequence in context: A040982 A040980 A040159 * A040974 A049557 A042991

Adjacent sequences:  A040168 A040169 A040170 * A040172 A040173 A040174

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane.

STATUS

approved

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Last modified August 1 19:36 EDT 2014. Contains 245137 sequences.