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%I #9 Mar 28 2018 08:14:01
%S 1,9,16,25,64,144,289,625,1369,2916,6241,13456,28900,62001,133225,
%T 286225,614656,1320201,2835856,6091024,13082689,28100601,60357361,
%U 129640996,278455969,598095936,1284648964,2759295841,5926690225,12729931929
%N Number of n X 3 binary arrays with each 1 adjacent to exactly one 0 vertically and one 0 horizontally.
%C Column 3 of A183352.
%H R. H. Hardin, <a href="/A183345/b183345.txt">Table of n, a(n) for n = 1..200</a>
%F Empirical: a(n) = a(n-1) + a(n-2) + 3*a(n-3) + a(n-4) - a(n-5) - a(n-6).
%F Empirical g.f.: x*(1 + 8*x + 6*x^2 - 3*x^3 - 5*x^4 - x^5) / ((1 + x^2 - x^3)*(1 - x - 2*x^2 - x^3)). - _Colin Barker_, Mar 28 2018
%e Some solutions for 5 X 3:
%e ..0..0..0....1..0..1....1..0..0....0..0..0....0..0..1....0..0..0....0..0..1
%e ..1..0..1....0..0..0....0..0..1....0..0..1....1..0..0....1..0..0....1..0..0
%e ..1..0..1....0..0..0....0..0..1....1..0..1....1..0..0....1..0..0....1..0..1
%e ..0..0..0....0..0..0....0..0..0....1..0..0....0..0..0....0..0..0....0..0..1
%e ..1..0..0....1..0..1....0..0..1....0..0..0....0..0..0....1..0..0....1..0..0
%Y Cf. A183352.
%K nonn
%O 1,2
%A _R. H. Hardin_, Jan 04 2011
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