This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A216745 #7 Sep 08 2022 08:46:03
%S A216745 5,7,13,17,23,29,31,37,41,43,47,53,61,71,79,97,101,103,109,113,127,
%T A216745 137,149,151,157,167,173,181,191,193,197,199,211,223,229,239,241,263,
%U A216745 269,271,277,281,293,311,313,317,337,349,359,367,373,379,383,389,397,401,409,421,431,433
%N A216745 Primes p such that x^28 = -2 has no solution mod p.
%C A216745 Complement of A051083 relative to A000040.
%H A216745 Vincenzo Librandi, <a href="/A216745/b216745.txt">Table of n, a(n) for n = 1..1000</a>
%t A216745 ok[p_]:= Reduce[Mod[x^28 + 2, p] == 0, x, Integers] == False; Select[Prime[Range[110]], ok]
%o A216745 (Magma) [p: p in PrimesUpTo(500) | not exists{x : x in ResidueClassRing(p) | x^28 eq -2} ]; // _Vincenzo Librandi_, Sep 16 2012
%Y A216745 Cf. A000040, A051083.
%K A216745 nonn,easy
%O A216745 1,1
%A A216745 _Vincenzo Librandi_, Sep 15 2012