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A207718 Number of 3 X n 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 0 1 and 1 0 0 vertically.

%I A207718 #8 Mar 05 2018 11:26:14
%S A207718 6,36,114,450,1644,6186,23010,85992,320742,1197318,4467984,16675494,
%T A207718 62232582,232257108,866792178,3234917538,12072868380,45056571498,
%U A207718 168153392514,627557039160,2342074698438,8740741860870,32620892573088
%N A207718 Number of 3 X n 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 0 1 and 1 0 0 vertically.
%C A207718 Row 3 of A207717.
%H A207718 R. H. Hardin, <a href="/A207718/b207718.txt">Table of n, a(n) for n = 1..210</a>
%F A207718 Empirical: a(n) = 2*a(n-1) + 7*a(n-2) - a(n-3) - 4*a(n-4) + a(n-5).
%F A207718 Empirical g.f.: 6*x*(1 + 4*x - 4*x^3 + x^4) / ((1 + x)*(1 - 4*x + x^2)*(1 + x - x^2)). - _Colin Barker_, Mar 05 2018
%e A207718 Some solutions for n=4:
%e A207718 ..0..1..0..0....1..1..1..1....1..1..1..0....1..1..0..1....1..1..0..1
%e A207718 ..0..1..1..0....1..1..1..1....0..1..1..0....0..1..0..0....0..1..1..0
%e A207718 ..0..1..1..0....1..1..1..0....1..0..1..0....1..1..0..1....1..1..0..1
%Y A207718 Cf. A207717.
%K A207718 nonn
%O A207718 1,1
%A A207718 _R. H. Hardin_, Feb 19 2012