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 A051970 #5 Mar 30 2012 16:48:43 %S A051970 74,218,493,565,1037,1565,1781,2138,2165,2173,3869,5165,5213,5837, %T A051970 6485,8021,10397,14213 %N A051970 Discriminants of real quadratic fields with class number 2 and related continued fraction period length of 5. %D A051970 R. A. Mollin, Quadratics, CRC Press, 1996, Appendix A, Table A3. %Y A051970 Cf. A051966-A051989. %Y A051970 Cf. A028488. %K A051970 nonn,fini,full %O A051970 1,1 %A A051970 _N. J. A. Sloane_, Jan 04 2000