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%I #9 Jul 02 2018 05:52:36
%S 26,676,2080,4212,7072,10660,14976,20020,25792,32292,39520,47476,
%T 56160,65572,75712,86580,98176,110500,123552,137332,151840,167076,
%U 183040,199732,217152,235300,254176,273780,294112,315172,336960,359476,382720
%N Number of n X 6 0..1 arrays avoiding 0 0 0 and 1 1 1 horizontally and 0 0 1 and 1 0 1 vertically.
%C Column 6 of A208379.
%H R. H. Hardin, <a href="/A208377/b208377.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 364*n^2 - 416*n + 52 for n>1.
%F Conjectures from _Colin Barker_, Jul 02 2018: (Start)
%F G.f.: 26*x*(1 + 23*x + 5*x^2 - x^3) / (1 - x)^3.
%F a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3) for n>4.
%F (End)
%e Some solutions for n=4:
%e ..1..1..0..0..1..0....1..1..0..1..0..0....1..1..0..1..0..0....1..0..1..0..0..1
%e ..1..1..0..0..1..0....1..1..0..1..1..0....0..1..1..0..1..0....0..0..1..1..0..1
%e ..0..1..0..0..1..0....1..0..0..1..0..0....0..0..1..0..1..0....0..0..1..1..0..0
%e ..0..1..0..0..1..0....1..0..0..1..0..0....0..0..1..0..1..0....0..0..1..1..0..0
%Y Cf. A208379.
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 25 2012
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