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%I #8 Mar 05 2018 05:23:26
%S 6,36,98,271,665,1675,4344,11081,28136,71908,183709,468421,1195165,
%T 3050758,7784759,19863812,50690966,129357269,330093729,842344955,
%U 2149538940,5485269169,13997500468,35719380356,91150094557,232600215969
%N Number of 3 X n 0..1 arrays avoiding 0 0 0 and 1 0 1 horizontally and 0 0 1 and 1 1 0 vertically.
%C Row 3 of A207305.
%H R. H. Hardin, <a href="/A207306/b207306.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = a(n-1) + a(n-2) + 6*a(n-3) + 4*a(n-4) + a(n-5) - 2*a(n-6) - 2*a(n-7) for n>9.
%F Empirical g.f.: x*(6 + 30*x + 56*x^2 + 101*x^3 + 56*x^4 + x^5 - 38*x^6 - 26*x^7 - 2*x^8) / (1 - x - x^2 - 6*x^3 - 4*x^4 - x^5 + 2*x^6 + 2*x^7). - _Colin Barker_, Mar 05 2018
%e Some solutions for n=4:
%e ..0..0..1..0....0..0..1..1....1..1..1..1....0..1..0..0....1..1..1..1
%e ..0..0..1..0....0..1..0..0....1..1..1..1....0..0..1..0....1..1..0..0
%e ..0..0..1..0....0..1..0..0....1..1..1..1....0..0..1..0....1..1..1..1
%Y Cf. A207305.
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 16 2012
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