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 A011987 #13 Feb 02 2020 21:33:25 %S A011987 1,6,12,30,50 %N A011987 Covering numbers C(n,6,5) (next term is <= 100). %D A011987 CRC Handbook of Combinatorial Designs, 1996, p. 263. %H A011987 D. Gordon, <a href="http://www.dmgordon.org/cover">La Jolla Repository of Coverings</a> %H A011987 K. J. Nurmela and Patric R. J. Östergård, <a href="http://www.tcs.hut.fi/old/papers/tp1.ps.Z">New coverings of t-sets with (t+1)-sets</a>, J. Combinat. Designs, 7 (1999), 217-226. %H A011987 K. J. Nurmela and Patric R. J. Östergård, <a href="http://www.tcs.hut.fi/old/papers/table3.html">New coverings of t-sets with (t+1)-sets (appendix)</a>, J. Combinat. Designs, 7 (1999), 217-226. %H A011987 <a href="/index/Cor#covnum">Index entries for covering numbers</a> %Y A011987 A column of A066010. %K A011987 nonn,hard %O A011987 6,2 %A A011987 _N. J. A. Sloane_