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%I #7 Mar 31 2012 12:36:03
%S 8,421,5004,54223,649826,7678409,91052720,1073661088,12644950311,
%T 149729950026,1765937206744,20858521172073,246298874943372,
%U 2908556504972388,34344854423802299,405576876056939440
%N Half the number of nX7 binary arrays with every element equal to exactly one or two of its horizontal and vertical neighbors
%C Column 7 of A185835
%H R. H. Hardin, <a href="/A185833/b185833.txt">Table of n, a(n) for n = 1..200</a>
%e Some solutions for 4X7 with a(1,1)=0
%e ..0..1..1..1..0..0..0....0..1..1..0..1..0..0....0..1..0..0..0..1..0
%e ..0..0..0..0..1..1..1....0..1..0..0..1..1..0....0..1..1..1..0..1..0
%e ..1..1..1..0..1..0..1....1..0..0..1..0..1..0....1..0..0..0..0..1..0
%e ..0..0..1..0..1..0..1....1..1..1..1..0..1..1....1..0..1..1..1..0..0
%K nonn
%O 1,1
%A _R. H. Hardin_ Feb 05 2011
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