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%I #12 Apr 19 2018 03:28:17
%S 6594,1411,3421,8983,11557,12895,14845,18415,25381,40279,63565,102591,
%T 161381,244087,372205,569647,861493,1322215,2039165,3110335,4775493,
%U 7347991,11212621,17186671,26409301,40358535,61856925,94997471,145320485
%N Number of (n+2) X 6 0..2 arrays with every 3 X 3 subblock commuting with each horizontal and vertical neighbor 3 X 3 subblock.
%C Column 4 of A186568.
%H R. H. Hardin, <a href="/A186563/b186563.txt">Table of n, a(n) for n = 1..200</a>
%F Empirical: a(n) = 2*a(n-1) - a(n-2) + 2*a(n-3) - 4*a(n-4) + 2*a(n-5) + 2*a(n-6) - 2*a(n-7) for n>12.
%F Empirical g.f.: x*(6594 - 11777*x + 7193*x^2 - 9636*x^3 + 20566*x^4 - 15622*x^5 - 19680*x^6 + 17962*x^7 + 1848*x^8 - 4416*x^9 + 6272*x^11) / ((1 - x)*(1 - x - 2*x^3 + 2*x^4 - 2*x^6)). - _Colin Barker_, Apr 18 2018
%e Some solutions for 4 X 6:
%e 1 0 0 0 0 2 1 0 0 0 2 1 2 0 0 0 2 0 0 0 0 0 0 2
%e 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
%e 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 0 0 0 0 0
%e 0 2 0 0 0 0 0 1 0 0 0 0 0 1 0 0 0 0 1 2 0 0 0 0
%Y Cf. A186568.
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 23 2011
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