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%I #18 Sep 08 2022 08:44:59
%S 2,3,11,17,41,43,59,83,89,107,113,131,137,179,227,233,251,257,281,283,
%T 347,353,401,419,443,449,457,467,491,499,521,563,569,587,593,601,617,
%U 641,643,659,683,691,761,809,827,857,881,929,947,953,971,977,1019,1049,1051,1091,1097,1163
%N Primes p such that x^54 = -2 has a solution mod p.
%C Complement of A216772 relative to A000040. - _Vincenzo Librandi_, Sep 17 2012
%H Vincenzo Librandi, <a href="/A051096/b051096.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[300]], ok] (* _Vincenzo Librandi_, Sep 16 2012 *)
%o (PARI)
%o forprime(p=2, 2000, if([]~!=polrootsmod(x^54+2, p), print1(p, ", "))); print();
%o /* _Joerg Arndt_, Jun 24 2012 */
%o (Magma) [p: p in PrimesUpTo(1200) | exists(t){x : x in ResidueClassRing(p) | x^54 eq - 2}]; // _Vincenzo Librandi_, Sep 16 2012
%K nonn,easy
%O 1,1
%A _N. J. A. Sloane_
%E More terms from _Joerg Arndt_, Jul 27 2011