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 A196435 #7 Jun 02 2025 04:24:10 %S A196435 13,178,1801,21803,246463,2856711,32855368,378154308,4356726770, %T A196435 50163397373,577634629068,6651858481248,76599144629883, %U A196435 882067405853789,10157379663581632,116966622243380304,1346919921065307751 %N A196435 Number of nX7 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 2,1,0,3,4 for x=0,1,2,3,4. %C A196435 Every 0 is next to 0 2's, every 1 is next to 1 1's, every 2 is next to 2 0's, every 3 is next to 3 3's, every 4 is next to 4 4's %C A196435 Column 7 of A196436 %H A196435 R. H. Hardin, <a href="/A196435/b196435.txt">Table of n, a(n) for n = 1..200</a> %e A196435 Some solutions for n=4 %e A196435 ..1..0..0..0..0..0..0....0..0..1..0..1..0..0....1..1..0..0..1..1..0 %e A196435 ..1..0..0..0..0..1..1....0..0..1..0..1..0..0....0..0..1..1..0..0..0 %e A196435 ..0..0..0..0..0..0..0....0..0..0..0..0..0..0....1..1..0..0..0..0..1 %e A196435 ..0..1..1..0..0..0..0....0..1..1..0..1..1..0....0..0..1..1..0..0..1 %K A196435 nonn %O A196435 1,1 %A A196435 _R. H. Hardin_ Oct 02 2011