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 A218950 #12 Jan 20 2018 17:36:44 %S A218950 1,1,1,1,2,3,3,5,6,7,9,12,17,20 %N A218950 Number of maximal nilpotent conjugacy classes of subgroups of the alternating group. %H A218950 Liam Naughton and Goetz Pfeiffer, <a href="http://arxiv.org/abs/1211.1911">Integer sequences realized by the subgroup pattern of the symmetric group</a>, arXiv:1211.1911 and <a href="https://cs.uwaterloo.ca/journals/JIS/VOL16/Naughton/naughton2.html">J. Int. Seq. 16 (2013) #13.5.8</a> %H A218950 Liam Naughton, <a href="http://www.maths.nuigalway.ie/~liam/CountingSubgroups.g">CountingSubgroups.g</a> %H A218950 Liam Naughton and Goetz Pfeiffer, <a href="http://schmidt.nuigalway.ie/tomlib/">Tomlib, The GAP table of marks library</a> %K A218950 nonn,more %O A218950 0,5 %A A218950 _Liam Naughton_, Nov 23 2012