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%I #6 Mar 31 2012 12:36:02
%S 21,13256,2792166,684657326,160107914496,38323943289566,
%T 9079893278572272,2159859526859795892
%N 1/3 the number of nX7 0..2 arrays with every element equal to exactly one or two of its horizontal and vertical neighbors
%C Column 7 of A185559
%e Some solutions for 4X7 with a(1,1)=0
%e ..0..0..0..1..1..2..2....0..0..0..1..1..2..2....0..0..1..1..2..2..1
%e ..0..1..0..1..0..0..0....0..1..0..2..2..0..2....0..1..0..1..2..2..1
%e ..0..1..0..1..0..2..2....0..1..0..2..1..0..2....0..1..0..1..0..0..2
%e ..0..0..0..2..2..1..1....0..0..0..1..1..2..2....0..0..0..1..1..2..2
%K nonn
%O 1,1
%A _R. H. Hardin_ Jan 31 2011