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Half the number of nX4 binary arrays with the number of 1-1 adjacencies equal to the number of 0-0 adjacencies
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%I #5 Mar 31 2012 12:35:50

%S 2,18,164,2101,29100,417190,6104168,90554742,1356933444,20489622108,

%T 311268434796,4751843588209,72836045462648,1120231330154058,

%U 17279391496374040,267199601139845596,4140858845912841972

%N Half the number of nX4 binary arrays with the number of 1-1 adjacencies equal to the number of 0-0 adjacencies

%C Column 4 of A183253

%H R. H. Hardin, <a href="/A183250/b183250.txt">Table of n, a(n) for n = 1..100</a>

%e Some solutions with a(1,1)=0 for 3X4

%e ..0..1..1..0....0..1..1..0....0..0..1..0....0..0..0..0....0..0..1..0

%e ..0..1..1..0....0..0..0..1....1..1..1..0....1..1..0..0....1..1..0..0

%e ..0..1..0..0....1..1..1..0....0..0..1..0....1..1..1..1....1..0..1..1

%K nonn

%O 1,1

%A _R. H. Hardin_ Jan 03 2011