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 A008575 #7 Jul 19 2021 01:17:35 %S A008575 1,18,4,13,6,10,15,2,17,3,19,7,16,8,11,14,9,12,5,20,25,50 %N A008575 Sectors on dartboard. %H A008575 K. S. Brown, <a href="http://www.mathpages.com/home/kmath025.htm">The Dartboard Sequence</a> %Y A008575 Cf. A003833. %K A008575 nonn,fini,full %O A008575 1,2 %A A008575 aubrey.moore(AT)saipan.com; C. R. Sloane