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 A040984 #30 Sep 08 2022 08:44:53
%S A040984 47,139,277,461,599,691,829,967,1013,1151,1289,1381,1427,1657,1933,
%T A040984 1979,2347,2393,2531,3037,3083,3221,3313,3359,3727,3911,4003,4049,
%U A040984 4463,4831,4877,4969,5107,5521,5659,5843,5981,6073,6211,6257,6763,6947,7039,7177
%N A040984 Primes p such that x^23 = 2 has no solution mod p.
%C A040984 Contribution from _Charles R Greathouse IV_, Sep 12 2012: (Start)
%C A040984 Complement of A049555 relative to A000040.
%C A040984 Terms of A212374 which are not in this sequence: 5153, 18539, 20747, 49681, 51199, 51797, 55201, 70381, .... (End)
%H A040984 Vincenzo Librandi, <a href="/A040984/b040984.txt">Table of n, a(n) for n = 1..1000</a>
%t A040984 Select[Prime[Range[PrimePi[7200]]], ! MemberQ[PowerMod[Range[#], 23, #], Mod[2, #]] &] (* _T. D. Noe_, Sep 13 2012 *)
%t A040984 ok[p_]:=Reduce[Mod[x^23 - 2, p]==0, x, Integers]==False; Select[Prime[Range[25000]], ok] (* _Vincenzo Librandi_, Sep 13 2012 *)
%o A040984 (Magma) [p: p in PrimesUpTo(8000) | forall{x: x in ResidueClassRing(p) | x^23 ne 2}]; // _Vincenzo Librandi_, Aug 21 2012
%o A040984 (PARI) select(n->!ispower(Mod(2,n),23),primes(1000)) \\ _Charles R Greathouse IV_, Sep 12 2012
%Y A040984 Cf. A000040, A049555.
%Y A040984 Cf. A212374.
%K A040984 nonn,easy
%O A040984 1,1
%A A040984 _Klaus Brockhaus_, Jan 20 2001