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 A211944 #14 Feb 22 2021 13:23:01 %S A211944 5,15,85,589,4512,37477,328718,2998039 %N A211944 Number of distinct finite languages over 3-ary alphabet, whose minimum regular expression has reverse Polish length 2n-1. %H A211944 Hermann Gruber, Jonathan Lee, and Jeffrey Shallit, <a href="http://arxiv.org/abs/1204.4982">Enumerating regular expressions and their languages</a>, arXiv:1204.4982v1 [cs.FL], 2012. %K A211944 nonn,hard %O A211944 1,1 %A A211944 _Hermann Gruber_, Apr 26 2012