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 A196947 #7 Jun 02 2025 04:38:16 %S A196947 12,496,9199,220433,5039158,115982718,2668162530,61397041229, %T A196947 1412800280934,32510004942226,748093522890152,17214334321208207, %U A196947 396117368115901278,9115043080958159524,209745995599652637243 %N A196947 Number of nX5 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 4,1,0,2,3 for x=0,1,2,3,4. %C A196947 Every 0 is next to 0 4's, every 1 is next to 1 1's, every 2 is next to 2 0's, every 3 is next to 3 2's, every 4 is next to 4 3's %C A196947 Column 5 of A196950 %H A196947 R. H. Hardin, <a href="/A196947/b196947.txt">Table of n, a(n) for n = 1..200</a> %e A196947 Some solutions for n=4 %e A196947 ..0..0..0..0..0....0..0..0..1..1....0..0..0..2..0....0..0..1..0..2 %e A196947 ..1..1..0..1..1....0..0..0..0..2....2..0..0..2..0....0..0..1..0..0 %e A196947 ..0..2..2..0..0....2..0..0..0..0....1..0..0..2..0....0..0..0..0..2 %e A196947 ..2..0..1..1..0....1..1..0..1..1....1..2..0..1..1....2..0..0..1..1 %K A196947 nonn %O A196947 1,1 %A A196947 _R. H. Hardin_ Oct 08 2011