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%I #13 Jun 19 2023 04:21:18
%S 11,41,61,71,131,151,181,211,241,251,271,311,331,401,461,491,521,571,
%T 601,631,641,661,691,751,761,811,821,881,911,941,971,991,1021,1031,
%U 1051,1061,1091,1171,1181,1291,1301
%N Primes p such that x^5 = 6 has no solution mod p.
%C Complement of A040169 relative to A000040. - _Vincenzo Librandi_, Sep 18 2012
%H Vincenzo Librandi, <a href="/A040170/b040170.txt">Table of n, a(n) for n = 1..1000</a>
%t ok[p_]:= Reduce[Mod[x^5 - 6, 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 6} ]; // _Vincenzo Librandi_, Sep 18 2012
%K nonn,easy
%O 1,1
%A _N. J. A. Sloane_