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 A185833 #9 Jul 22 2025 10:03:18 %S A185833 8,421,5004,54223,649826,7678409,91052720,1073661088,12644950311, %T A185833 149729950026,1765937206744,20858521172073,246298874943372, %U A185833 2908556504972388,34344854423802299,405576876056939440 %N A185833 Half the number of nX7 binary arrays with every element equal to exactly one or two of its horizontal and vertical neighbors. %C A185833 Column 7 of A185835 %H A185833 R. H. Hardin, <a href="/A185833/b185833.txt">Table of n, a(n) for n = 1..200</a> %e A185833 Some solutions for 4X7 with a(1,1)=0 %e A185833 ..0..1..1..1..0..0..0....0..1..1..0..1..0..0....0..1..0..0..0..1..0 %e A185833 ..0..0..0..0..1..1..1....0..1..0..0..1..1..0....0..1..1..1..0..1..0 %e A185833 ..1..1..1..0..1..0..1....1..0..0..1..0..1..0....1..0..0..0..0..1..0 %e A185833 ..0..0..1..0..1..0..1....1..1..1..1..0..1..1....1..0..1..1..1..0..0 %K A185833 nonn %O A185833 1,1 %A A185833 _R. H. Hardin_ Feb 05 2011