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 A299116 #34 Feb 23 2018 07:41:20 %S A299116 0,0,0,2,27,3133,5777931 %N A299116 The number of sparse union-closed sets. That is, the number of union-closed sets on n elements containing the empty set and the universe, such that in average each set (not counting the empty set) has at most n/2 elements. %C A299116 If there is a counterexample to the union-closed set conjecture, it is a sparse union-closed set. %H A299116 G. Brinkmann and R. Deklerck, <a href="https://arxiv.org/abs/1701.03751"> Generation of Union-Closed Sets and Moore Families</a>, arXiv:1701.03751 [math.CO], 2017. %H A299116 G. Brinkmann and R. Deklerck, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL21/Brinkmann/brink6.html"> Generation of Union-Closed Sets and Moore Families</a>, Journal of Integer Sequences, Vol.21 (2018), Article 18.1.7. %Y A299116 Cf. A108798, A102894, A193674, A102896. %K A299116 nonn,more %O A299116 1,4 %A A299116 _Gunnar Brinkmann_, Feb 05 2018