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 A126737 #9 Aug 15 2019 16:50:43 %S A126737 0,0,1,2,12,64,475,5036,80947,2010328,76115143 %N A126737 Number of connected graphs on n nodes with chromatic number 3. %H A126737 Keith M. Briggs, <a href="http://keithbriggs.info/cgt.html">Combinatorial Graph Theory</a> %Y A126737 A diagonal of triangle in A126736. %K A126737 nonn %O A126737 1,4 %A A126737 _N. J. A. Sloane_, Feb 16 2007 %E A126737 a(11) from _Michael Sollami_, Jan 29 2012