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 A051989 #7 Sep 21 2021 07:25:43 %S A051989 826,871,1147,1255,1614,1711,1795,2051,2119,2154,2409,2414,2534,2594, %T A051989 2698,2743,2759,3009,3018,3110,3206,3633,3806,3854,3882,4031,4118, %U A051989 4310,4638,4665,4826,5322,5466,6155,6302,6455,6618,7091,7222 %N A051989 Discriminants of real quadratic fields with class number 2 and related continued fraction period length of 24. %D A051989 R. A. Mollin, Quadratics, CRC Press, 1996, Appendix A, Table A3. %H A051989 Georg Fischer, <a href="/A051989/b051989.txt">Table of n, a(n) for n = 1..176</a> %Y A051989 Cf. A051966-A051989. %K A051989 nonn,fini,full %O A051989 1,1 %A A051989 _N. J. A. Sloane_, Jan 04 2000