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 A133435 #8 Aug 04 2018 02:52:24 %S A133435 3,7,23,71,311,479,1559,5711,10559,18191,31391,422231,701399,3818929, %T A133435 9257329,22000801,36415991,48473881,175244281,427733329,3389934071, %U A133435 7979490791,36504256799,89206899239,121560956039,395668053479,513928659191,5528920734431,8402847753431,70864718555231 %N A133435 Records in A000229. %H A133435 Tomás Oliveira e Silva, <a href="http://sweet.ua.pt/tos/p_roots.html">Least primitive root of prime numbers</a> %K A133435 nonn %O A133435 1,1 %A A133435 _N. J. A. Sloane_, Nov 29 2007