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%I #11 Sep 13 2018 08:24:48
%S 4,5,36,97,411,1394,5223,18708,68348,247545,899960,3266477,11864371,
%T 43080054,156446379,568106600,2063027108,7491613757,27204943788,
%U 98791463513,358749562651,1302756292618,4730805017359,17179356326908
%N Number of 3 X n binary arrays with top left element equal to 1 and no two ones adjacent horizontally or nw-se.
%H R. H. Hardin, <a href="/A228798/b228798.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = a(n-1) + 8*a(n-2) + 6*a(n-3) - a(n-4) - a(n-5).
%F Empirical g.f.: x*(4 + x - x^2 - 3*x^3) / ((1 + x)*(1 - 2*x - 6*x^2 + x^4)). - _Colin Barker_, Sep 13 2018
%e Some solutions for n=4:
%e ..1..0..1..0....1..0..0..0....1..0..0..1....1..0..0..0....1..0..0..1
%e ..0..0..1..0....0..0..0..0....0..0..0..1....1..0..1..0....1..0..0..1
%e ..1..0..1..0....0..0..1..0....1..0..0..1....0..0..1..0....1..0..0..1
%Y Row 3 of A228796.
%K nonn
%O 1,1
%A _R. H. Hardin_, Sep 04 2013
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