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 A323472 #13 Apr 30 2021 21:26:14 %S A323472 -1,2083,7080,10846,25962,22420,202890,142678,252952,188500,257478, %T A323472 604327,667826,57216,115496,231929,203330,283650,426850,153520,231298, %U A323472 142266,236486,149871,204526,215032,285982,188081,153460,128801,213852,202258,94966,224777 %N A323472 On a spirally numbered square grid, with labels starting at 0, this is the number of the last cell that a (1,n) leaper reaches before getting trapped, or -1 if it never gets trapped. %C A323472 A (1,2) leaper is a chess knight. %C A323472 a(2)-a(5) were computed by _Daniël Karssen_. %H A323472 Rémy Sigrist, <a href="/A323472/b323472.txt">Table of n, a(n) for n = 1..1000</a> %H A323472 Rémy Sigrist, <a href="/A323472/a323472.png">Figure showing the complete figure for a (1, 624) leaper</a> (where the color is function of the time) %H A323472 Rémy Sigrist, <a href="/A323472/a323472.txt">C++ program for A323472</a> %H A323472 N. J. A. Sloane and Brady Haran, <a href="https://www.youtube.com/watch?v=RGQe8waGJ4w">The Trapped Knight</a>, Numberphile video (2019) %o A323472 (C++) See Links section. %Y A323472 The sequences involved in this set of related sequences are A316884, A316967, A316667, A316328, A317106, A317105, A317416, A317415, A317438, A317437, and A323469, A323470, A323471, A323472. %K A323472 sign %O A323472 1,2 %A A323472 _N. J. A. Sloane_, Jan 28 2019 %E A323472 More terms from _Rémy Sigrist_, Jan 29 2019