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 A343540 #10 Apr 20 2021 22:58:09 %S A343540 1,10,7,6,5,4,3,12,13,8,9,44,45,42,41,40,39,18,17,16,15,14,11,26,27, %T A343540 28,29,30,31,34,33,32,35,62,61,38,37,64,63,98,97,96,95,94,93,56,53,50, %U A343540 47,114,73,154,109,108,107,106,105,104,103,102 %N A343540 Squares visited by a trapped knight on a square-spiral numbered board where the knight is shifted one square up and one square to the right after each move. %C A343540 The squares are numbered starting with 1 at the origin (0,0). The sequence is finite: when arriving on square number a(180) = 157, there is no free square within reach for the next move. %C A343540 Shifting the knight only 1 square to the right leads to an infinite sequence. Similarly, shifting only 1 square up leads to an infinite sequence. More generally, if the knight jumps (1,n) spaces and is shifted m squares to the right, m > n leads to an infinite sequence. %H A343540 N. J. A. Sloane and Brady Haran, <a href="https://www.youtube.com/watch?v=RGQe8waGJ4w">The Trapped Knight</a>, Numberphile video (2019). %K A343540 nonn,fini %O A343540 1,2 %A A343540 _Simon S. Gurvets_, Apr 18 2021