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 A316884 #14 Aug 18 2019 04:30:50 %S A316884 1,3,11,9,23,7,19,5,15,33,13,29,53,27,25,47,77,45,21,41,69,39,17,35, %T A316884 61,95,59,31,55,87,127,85,51,49,79,117,163,115,75,43,71,107,151,105, %U A316884 67,37,63,97,139,189,137,93,57,89,129,177,233,175,125,83,81,119 %N A316884 Squares visited by moving diagonally one square on a spirally numbered board and moving to the lowest available unvisited square at each step. %C A316884 Board is numbered with the square spiral: %C A316884 . %C A316884 17--16--15--14--13 %C A316884 | | %C A316884 18 5---4---3 12 . %C A316884 | | | | %C A316884 19 6 1---2 11 . %C A316884 | | | %C A316884 20 7---8---9--10 . %C A316884 | %C A316884 21--22--23--24--25--26 %H A316884 Daniël Karssen, <a href="/A316884/b316884.txt">Table of n, a(n) for n = 1..10000</a> %H A316884 Daniël Karssen, <a href="/A316884/a316884.svg">Figure showing the first 49 steps of the sequence</a> %Y A316884 Cf. A316667, A316671. %K A316884 nonn %O A316884 1,2 %A A316884 _Daniël Karssen_, Jul 15 2018