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%I #9 Apr 04 2018 10:47:57
%S 13,47,161,567,1969,6887,24001,83799,292305,1020103,3559137,12419383,
%T 43333873,151206055,527598593,1840949015,6423592977,22413786247,
%U 78208138529,272890816759,952194714417,3322482302055,11593099229761
%N Half the number of (n+1) X 3 binary arrays with no 2 X 2 subblock having exactly 2 ones.
%C Column 2 of A183782.
%H R. H. Hardin, <a href="/A183775/b183775.txt">Table of n, a(n) for n = 1..200</a>
%F Empirical: a(n) = 3*a(n-1) + 4*a(n-2) - 8*a(n-3).
%F Empirical g.f.: x*(13 + 8*x - 32*x^2) / (1 - 3*x - 4*x^2 + 8*x^3). - _Colin Barker_, Apr 04 2018
%e Some solutions with a(1,1)=0 for 5 X 3:
%e ..0..1..0....0..1..1....0..0..0....0..1..0....0..1..0....0..0..0....0..0..0
%e ..1..1..1....1..1..1....1..0..1....1..1..1....1..1..1....0..0..1....0..0..0
%e ..1..0..1....1..1..1....0..0..0....1..1..1....1..0..1....0..1..1....1..0..0
%e ..0..0..0....1..1..0....0..0..0....1..1..1....0..0..0....1..1..1....1..1..0
%e ..0..0..0....1..1..1....0..1..0....1..1..1....1..0..0....1..1..0....1..1..1
%Y Cf. A183782.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 07 2011
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