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%I #8 May 03 2018 09:59:11
%S 415,155,274,458,578,670,790,966,1242,1702,2338,3247,4460,6025,8139,
%T 11017,14883,20207,27508,37362,50788,69069,93769,127365,173117,235142,
%U 319489,434273,590030,801705,1089569,1480431,2011558,2733658,3714513
%N Number of (n+2) X 6 binary arrays with every 3 X 3 subblock commuting with each horizontal and vertical neighbor 3 X 3 subblock.
%C Column 4 of A190033.
%H R. H. Hardin, <a href="/A190028/b190028.txt">Table of n, a(n) for n = 1..200</a>
%F Empirical: a(n) = 2*a(n-1) -a(n-2) +a(n-3) -2*a(n-4) +a(n-5) +a(n-6) -a(n-7) for n>12.
%F Empirical g.f.: x*(415 - 675*x + 379*x^2 - 350*x^3 + 611*x^4 - 407*x^5 - 452*x^6 + 380*x^7 + 9*x^8 - 28*x^9 + 81*x^11) / ((1 - x)*(1 - x - x^3 + x^4 - x^6)). - _Colin Barker_, May 03 2018
%e Some solutions for 4 X 6:
%e ..1..0..0..0..0..0....0..0..0..0..0..1....0..0..0..0..1..0....0..0..0..0..0..0
%e ..0..0..0..0..0..1....0..0..0..0..0..1....0..0..0..0..0..0....0..0..0..0..0..1
%e ..0..0..0..0..0..0....1..0..0..0..0..1....1..0..0..0..0..0....1..0..0..0..0..0
%e ..0..1..0..0..0..0....1..0..0..0..0..1....0..1..0..0..0..0....0..0..0..0..0..0
%Y Cf. A190033.
%K nonn
%O 1,1
%A _R. H. Hardin_, May 04 2011
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