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 A230090 #10 Aug 11 2018 10:43:59 %S A230090 1,1,1,1,1,1,2,2,5,11,35635 %N A230090 A certain restricted class of posets on n points. %C A230090 See Guay-Paquet for precise definition. %H A230090 M. Guay-Paquet, <a href="https://arxiv.org/abs/1306.2400">A modular relation for the chromatic symmetric functions of (3+1)-free posets</a>, arXiv preprint arXiv:1306.2400 [math.CO], 2013. %Y A230090 Cf. A000112, A079146. %K A230090 nonn,more %O A230090 1,7 %A A230090 _N. J. A. Sloane_, Oct 09 2013