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 A160877 #2 Mar 30 2012 16:51:24 %S A160877 0,3,84,1680,29760 %N A160877 Regular coverings having dihedral voltage groups: see Kwak-Lee reference in A160870 for precise definition. %K A160877 nonn %O A160877 1,2 %A A160877 _N. J. A. Sloane_, Nov 15 2009