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%I #5 Mar 31 2012 12:36:06
%S 277659,21661,37576,121144,260584,338176,443560,571984,798832,1272712,
%T 2086288,3350152,5585728,9225664,15403771,25918654,43087345,71662141,
%U 119953993,199127077,331052797,553674334,920445640,1531199242,2558915851
%N Number of (n+2)X9 0..3 arrays with every 3X3 subblock commuting with each horizontal and vertical neighbor 3X3 subblock
%C Column 7 of A186881
%H R. H. Hardin, <a href="/A186879/b186879.txt">Table of n, a(n) for n = 1..200</a>
%F Empirical: a(n)=2*a(n-1)-a(n-2)+3*a(n-3)-6*a(n-4)+3*a(n-5)+3*a(n-6)-3*a(n-7) for n>15
%e Some solutions for 4X9
%e ..1..0..0..0..0..0..0..2..3....0..0..0..0..0..0..0..1..3
%e ..0..0..0..0..0..0..0..0..0....3..0..0..0..0..0..0..0..1
%e ..0..0..0..0..0..0..0..0..0....0..3..0..0..0..0..0..0..0
%e ..0..1..0..0..0..0..0..0..0....2..0..3..0..0..0..0..0..0
%K nonn
%O 1,1
%A _R. H. Hardin_ Feb 28 2011
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