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Primes p such that x^5 = 11 has no solution mod p.
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%I #15 Jun 19 2023 07:24:02

%S 31,41,71,101,131,151,181,211,251,271,281,331,401,421,431,461,491,521,

%T 571,601,631,641,701,761,811,821,881,941,971,991,1021,1031,1051,1061,

%U 1091,1151,1171,1201,1321,1361

%N Primes p such that x^5 = 11 has no solution mod p.

%C Complement of A040179 relative to A000040. - _Vincenzo Librandi_, Sep 18 2012

%H Vincenzo Librandi, <a href="/A040180/b040180.txt">Table of n, a(n) for n = 1..1000</a>

%t ok[p_]:= Reduce[Mod[x^5 - 11, p] == 0, x, Integers] == False; Select[Prime[Range[300]], ok] (* _Vincenzo Librandi_, Sep 18 2012 *)

%o (Magma) [p: p in PrimesUpTo(1500) | not exists{x : x in ResidueClassRing(p) | x^5 eq 11} ]; // _Vincenzo Librandi_, Sep 18 2012

%Y Cf. A000040, A040179.

%K nonn,easy

%O 1,1

%A _N. J. A. Sloane_