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 A222184 #11 Apr 30 2017 08:08:15
%S A222184 11,43,59,71,79,97,103,137,263,331,349,359,421,433,487,523,653,659,
%T A222184 743,859,863,907,919,983,1069,1087,1091,1093,1163,1223,1229,1279,1381,
%U A222184 1483,1499,1549,1657,1663,1667,1697,1747,1777,1787,1789,1877,1993,2011,2213,2221,2251,2281,2309,2371,2393,2473,2671,2719,2777,2791,2803,2833,2861,3037,3079,3163,3251,3257,3463,3511,3557
%N A222184 Primes p such that q^(p-1) == 1 (mod p^2) for some prime q < p.
%C A222184 Subsequence of A134307; see its interesting heuristics. (What is the analogous heuristic for the present sequence?)
%C A222184 The smallest corresponding primes q are A222185.
%D A222184 L. E. Dickson, History of the Theory of Numbers, vol. 1, chap. IV.
%H A222184 Giovanni Resta, <a href="/A222184/b222184.txt">Table of n, a(n) for n = 1..10000</a>
%H A222184 W. Keller and J. Richstein, <a href="http://web.archive.org/web/20091109011757/http://www1.uni-hamburg.de/RRZ/W.Keller/FermatQuotient.html">Fermat quotients that are divisible by p</a>.
%F A222184 A222185(n)^(a(n)-1) == 1 (mod a(n)^2).
%e A222184 3 is a prime < 11, and 11^2 divides 3^(11-1)-1 = 59048 = 121*488, so 11 is a member.
%t A222184 Select[ Prime[ Range[500]], Product[ PowerMod[ Prime[k], # - 1, #^2] - 1, {k, 1, PrimePi[#] - 1}] == 0 &]
%o A222184 (PARI) lista(nn) = {forprime (p=2, nn, ok = 0; forprime(q=2, p-1, if (Mod(q, p^2)^(p-1) == 1, ok=1; break);); if (ok, print1(p, ", ")););} \\ _Michel Marcus_, Nov 24 2014
%Y A222184 Cf. A001220, A039678, A134307, A143548, A222185.
%K A222184 nonn
%O A222184 1,1
%A A222184 _Jonathan Sondow_, Feb 11 2013