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%I #5 Mar 31 2012 12:37:30
%S 428676,182095128,76648760118,32342700329739,13642480312938969,
%T 5755153225046584062,2427793108137633168210,1024163896230568622499099,
%U 432042536759800714389833904,182256830990255873542213582497
%N Half the number of (n+1)X7 0..2 arrays with every 2X2 subblock having exactly one duplicate clockwise edge difference
%C Column 6 of A209796
%H R. H. Hardin, <a href="/A209794/b209794.txt">Table of n, a(n) for n = 1..210</a>
%e Some solutions for n=4
%e ..0..1..0..2..2..2..0....1..0..1..2..0..1..1....1..1..2..0..2..2..0
%e ..1..1..0..1..1..2..1....2..0..2..2..2..1..2....1..2..2..1..1..1..1
%e ..0..1..1..1..2..2..1....2..2..2..0..0..1..2....1..0..0..0..1..2..1
%e ..0..0..0..0..2..0..1....1..0..1..0..1..1..2....0..0..1..0..2..2..1
%e ..0..1..2..0..0..0..1....0..0..0..0..0..2..2....0..2..2..2..2..0..0
%K nonn
%O 1,1
%A _R. H. Hardin_ Mar 13 2012