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 A051974 #4 Mar 30 2012 16:48:43 %S A051974 106,698,1073,1189,1285,1385,1418,1865,2581,3233,4469,4553,4709,5597, %T A051974 8885,9365,9773,9893,10229,10685,12053,12077,13565,14285,16733,23285, %U A051974 28757,29957 %N A051974 Discriminants of real quadratic fields with class number 2 and related continued fraction period length of 9. %D A051974 R. A. Mollin, Quadratics, CRC Press, 1996, Appendix A, Table A3. %Y A051974 Cf. A051966-A051989. %K A051974 nonn,fini,full %O A051974 1,1 %A A051974 _N. J. A. Sloane_, Jan 04 2000