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%I #8 Apr 17 2018 14:13:22
%S 106,128,270,449,797,1061,1681,2285,3681,5281,8437,12401,19317,28641,
%T 44073,65877,100705,151229,230209,346689,526453,794241,1204293,
%U 1818849,2755433,4164309,6305265,9533069,14429537,21821729,33023541,49948881
%N Number of (n+1) X 6 binary arrays with every 2 X 2 subblock commuting with each of its horizontal and vertical 2 X 2 subblock neighbors.
%C Column 5 of A186462.
%H R. H. Hardin, <a href="/A186458/b186458.txt">Table of n, a(n) for n = 1..200</a>
%F Empirical: a(n) = 2*a(n-1) - 2*a(n-3) + 2*a(n-4) - a(n-5) for n>11.
%F Empirical g.f.: x*(106 - 84*x + 14*x^2 + 121*x^3 - 57*x^4 - 143*x^5 + 45*x^6 - 111*x^7 + 88*x^8 - 44*x^9 + 144*x^10) / ((1 - x)*(1 - x - x^2 + x^3 - x^4)). - _Colin Barker_, Apr 17 2018
%e Some solutions for 3 X 6:
%e ..1..1..0..0..0..0....0..0..0..0..1..1....0..0..0..0..0..0....0..0..1..0..1..0
%e ..0..0..1..0..0..0....0..0..0..0..0..1....1..0..0..0..0..0....0..0..0..1..0..1
%e ..0..0..0..1..1..1....0..0..0..0..0..0....1..1..0..0..0..1....0..0..0..0..1..0
%Y Cf. A186462.
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 22 2011
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