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 A196453 #7 Jun 02 2025 04:24:31 %S A196453 8,67,383,2930,27320,249402,2032584,15952022,128543371,1060801262, %T A196453 8803139813,72685286254,596527548372,4887671652328,40110935638661, %U A196453 329698087638675,2710883854573401,22279902843871853,183037488877957616 %N A196453 Number of nX5 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 3,0,2,4,1 for x=0,1,2,3,4. %C A196453 Every 0 is next to 0 3's, every 1 is next to 1 0's, every 2 is next to 2 2's, every 3 is next to 3 4's, every 4 is next to 4 1's %C A196453 Column 5 of A196456 %H A196453 R. H. Hardin, <a href="/A196453/b196453.txt">Table of n, a(n) for n = 1..200</a> %e A196453 Some solutions for n=4 %e A196453 ..1..1..1..1..0....1..0..0..1..1....2..2..2..2..0....0..1..1..0..0 %e A196453 ..0..0..0..1..1....1..1..1..1..0....2..0..0..2..0....0..1..2..2..0 %e A196453 ..0..0..0..2..2....0..1..2..2..0....2..2..0..2..0....1..1..2..2..0 %e A196453 ..1..1..1..2..2....0..1..2..2..0....0..2..2..2..1....1..0..0..0..0 %K A196453 nonn %O A196453 1,1 %A A196453 _R. H. Hardin_ Oct 02 2011