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%I #9 Sep 02 2013 13:01:06
%S 8,40,216,1152,6160,32928,176032,941056,5030848,26894720,143778176,
%T 768632832,4109082880,21967006208,117434808832,627802177536,
%U 3356207397888,17942161561600,95918137153536,512774840614912
%N Number of nX4 binary arrays with no two ones adjacent horizontally, diagonally or antidiagonally.
%C Column 4 of A228683
%H R. H. Hardin, <a href="/A228679/b228679.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 6*a(n-1) -2*a(n-2) -8*a(n-3).
%F Empirical: G.f. -8*x*(-1+x+x^2) / ( 1-6*x+2*x^2+8*x^3 ). - _R. J. Mathar_, Aug 31 2013
%e Some solutions for n=4
%e ..0..0..1..0....0..1..0..1....1..0..0..0....0..0..0..1....1..0..0..1
%e ..0..0..0..0....0..0..0..1....0..0..0..1....1..0..0..0....1..0..0..0
%e ..1..0..1..0....1..0..0..0....0..0..0..1....1..0..0..1....0..0..0..0
%e ..1..0..1..0....0..0..0..0....1..0..0..1....1..0..0..0....1..0..0..0
%K nonn
%O 1,1
%A _R. H. Hardin_ Aug 30 2013
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