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%I #3 Mar 31 2012 12:35:49
%S 7,49,230,1209,6475,34020,179097,944514,4978956,26241679,138316703,
%T 729070278,3842881010,20255521442,106765644778,562755120940,
%U 2966245831625,15634892911279,82410528967137,434380653636920
%N Number of nX3 binary matrices with no three 1's adjacent in a line horizontally, vertically, diagonally or antidiagonally
%C Column 3 of A181224
%H R. H. Hardin, <a href="/A181219/b181219.txt">Table of n, a(n) for n=1..350</a>
%F Empirical: a(n)=2*a(n-1)+8*a(n-2)+38*a(n-3)+51*a(n-4)+41*a(n-5)-48*a(n-6)-88*a(n-7)-4*a(n-8)-8*a(n-9)-15*a(n-10)+14*a(n-11)-7*a(n-12)+a(n-13)-2*a(n-14)
%e Some avoided solutions for 4X3
%e ..1..0..0....1..1..0....1..0..0....1..0..0....0..0..1....0..0..0....0..0..1
%e ..0..1..0....0..1..0....0..0..1....0..1..0....0..1..0....0..0..0....0..1..0
%e ..0..0..1....0..0..1....0..1..0....0..0..1....1..0..1....0..0..1....1..0..0
%e ..0..1..0....0..0..0....1..0..0....1..0..0....0..0..0....1..1..1....0..0..1
%K nonn
%O 1,1
%A _R. H. Hardin_ Oct 10 2010
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