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 A268534 #5 Feb 22 2016 13:01:39 %S A268534 2,6,84,43918 %N A268534 Size of free Kleene algebra on n generators. %D A268534 J. Berman and P. Koehler, Cardinalities of finite distributive lattices, Mitteilungen aus dem Mathematischen Seminar Giessen, 121 (1976), 103-124. %H A268534 J. Berman and P. Koehler, <a href="/A006356/a006356.pdf">Cardinalities of finite distributive lattices</a>, Mitteilungen aus dem Mathematischen Seminar Giessen, 121 (1976), 103-124. [Annotated scanned copy] %K A268534 nonn,more %O A268534 0,1 %A A268534 _N. J. A. Sloane_, Feb 22 2016