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%I #7 Sep 08 2022 08:46:03
%S 5,7,13,19,23,29,31,37,47,53,61,67,71,73,79,97,101,103,109,127,139,
%T 149,151,157,163,167,173,181,191,193,197,199,211,223,229,239,241,263,
%U 269,271,277,293,307,311,313,317,331,337,349,359,367,373,379,383,389
%N Primes p such that x^54 = -2 has no solution mod p.
%C Complement of A051096 relative to A000040.
%H Vincenzo Librandi, <a href="/A216772/b216772.txt">Table of n, a(n) for n = 1..1000</a>
%t ok[p_] := Reduce[Mod[x^54 + 2, p] == 0, x, Integers] == False;Select[Prime[Range[200]], ok]
%o (Magma) [p: p in PrimesUpTo(600) | not exists{x: x in ResidueClassRing(p) | x^54 eq -2}];
%Y Cf. A000040, A051096.
%K nonn,easy
%O 1,1
%A _Vincenzo Librandi_, Sep 16 2012