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Primes p such that x^5 = 12 has no solution mod p.
2

%I #16 Jun 19 2023 06:40:19

%S 31,41,61,71,101,131,151,181,191,241,251,281,311,331,401,421,461,491,

%T 521,541,571,601,631,641,661,691,701,751,761,821,881,911,971,991,1021,

%U 1031,1051,1061,1091,1151,1171

%N Primes p such that x^5 = 12 has no solution mod p.

%C Complement of A040184 relative to A000040. - _Vincenzo Librandi_, Sep 18 2012

%H Vincenzo Librandi, <a href="/A040969/b040969.txt">Table of n, a(n) for n = 1..1000</a>

%t ok[p_]:= Reduce[Mod[x^5 - 12, 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 12} ]; // _Vincenzo Librandi_, Sep 18 2012

%Y Cf. A000040, A040184.

%K nonn,easy

%O 1,1

%A _N. J. A. Sloane_