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 A059668 #12 Sep 08 2022 08:45:03
%S A059668 919,1423,1999,2143,2287,2791,4177,4519,4663,5113,5167,6679,6967,8713,
%T A059668 9631,9649,9721,11863,12241,12583,12799,13591,16111,17551,18127,20359,
%U A059668 20719,21529,21727,21799,22807,23041,23473,23743,23833,23887,23977
%N A059668 Primes p such that x^36 = 2 has no solution mod p, but x^12 = 2 has a solution mod p.
%H A059668 Vincenzo Librandi, <a href="/A059668/b059668.txt">Table of n, a(n) for n = 1..357</a>
%t A059668 Select[Prime[Range[PrimePi[30000]]], ! MemberQ[PowerMod[Range[#], 36, #], Mod[2, #]]&& MemberQ[PowerMod[Range[#], 12, #], Mod[2, #]] &] (* _Vincenzo Librandi_, Sep 22 2013 *)
%o A059668 (Magma) [p: p in PrimesUpTo(24000) | not exists{x: x in ResidueClassRing(p) | x^36 eq 2} and exists{x: x in ResidueClassRing(p) | x^12 eq 2}]; // _Vincenzo Librandi_, Sep 21 2012
%Y A059668 A000040, A049568, A049544, A059264.
%K A059668 nonn,easy
%O A059668 1,1
%A A059668 _Klaus Brockhaus_, Feb 04 2001