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%I #9 Mar 29 2018 05:30:41
%S 3,13,29,89,273,751,2221,6485,18647,54395,157947,457879,1330821,
%T 3863375,11214839,32568969,94558013,274542857,797165417,2314532695,
%U 6720246173,19512370773,56654003695,164495136155,477612471027,1386747980543
%N Number of n X 3 binary arrays with every 1 having exactly one king-move neighbor equal to 1.
%C Column 3 of A183442.
%H R. H. Hardin, <a href="/A183436/b183436.txt">Table of n, a(n) for n = 1..200</a>
%F Empirical: a(n) = a(n-1) + 3*a(n-2) + 8*a(n-3) - a(n-4) - 2*a(n-5) - 2*a(n-6).
%F Empirical g.f.: x*(3 + 10*x + 7*x^2 - 3*x^3 - 4*x^4 - 2*x^5) / (1 - x - 3*x^2 - 8*x^3 + x^4 + 2*x^5 + 2*x^6). - _Colin Barker_, Mar 29 2018
%e Some solutions for 5 X 3.
%e ..0..0..0....0..1..0....0..0..1....1..0..0....1..0..0....0..0..0....1..0..0
%e ..0..1..0....0..1..0....0..1..0....1..0..0....1..0..1....0..0..0....1..0..0
%e ..1..0..0....0..0..0....0..0..0....0..0..0....0..0..1....0..1..1....0..0..0
%e ..0..0..1....0..0..0....0..0..1....0..0..1....0..0..0....0..0..0....1..0..0
%e ..0..0..1....0..1..1....0..0..1....0..1..0....0..0..0....1..1..0....0..1..0
%Y Cf. A183442.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 04 2011
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