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 A196580 #20 Aug 14 2020 13:26:35 %S A196580 57,81,77,111,91,146,120 %N A196580 Length of longest possible 72-degree snake inside a circle of diameter n. %C A196580 A snake is a sequence of unit line segments that are non-overlapping except that each one begins where the previous one ends. An n-degree snake is a snake all of whose multiples with the horizontal are multiples of n. %H A196580 Erich Friedman, <a href="https://erich-friedman.github.io/mathmagic/0503.html">Problem of the month May 2003</a> %K A196580 more,nonn %O A196580 5,1 %A A196580 _Kausthub Gudipati_, Oct 04 2011