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 A196854 #7 Jun 02 2025 04:35:14 %S A196854 22,1792,56470,2369631,94652804,3805929995,152929723254,6148984299163, %T A196854 247223213832440,9939022894905148,399570539750626195, %U A196854 16063726580619196531,645804489432297174658,25963059069129330544089 %N A196854 Number of nX6 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 3,1,0,2,4 for x=0,1,2,3,4. %C A196854 Every 0 is next to 0 3'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 4's %C A196854 Column 6 of A196856 %H A196854 R. H. Hardin, <a href="/A196854/b196854.txt">Table of n, a(n) for n = 1..172</a> %e A196854 Some solutions for n=4 %e A196854 ..0..0..1..0..0..2....0..0..2..0..1..1....0..0..0..2..0..1....0..0..0..2..0..0 %e A196854 ..0..0..1..2..1..0....0..0..2..2..0..0....0..0..1..1..0..1....0..0..1..1..0..1 %e A196854 ..0..1..0..0..1..2....0..0..0..2..2..2....0..0..2..0..0..0....0..1..0..0..2..1 %e A196854 ..0..1..2..0..0..0....2..0..0..0..0..0....0..0..1..1..0..0....0..1..0..0..2..0 %K A196854 nonn %O A196854 1,1 %A A196854 _R. H. Hardin_ Oct 06 2011