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%I #8 Jun 26 2018 14:08:51
%S 9,81,279,1377,5895,26685,118179,527913,2350215,10476981,46680363,
%T 208028817,926993439,4130894781,18407971395,82029484089,365538508695,
%U 1628908337349,7258719524571,32346212936481,144140772230991
%N Number of 4 X n 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 0 0 and 1 0 1 vertically.
%C Row 4 of A208028.
%H R. H. Hardin, <a href="/A208029/b208029.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 2*a(n-1) + 11*a(n-2) + 2*a(n-3) - 10*a(n-4).
%F Empirical g.f.: 9*x*(1 - x)*(1 + 8*x + 10*x^2) / (1 - 2*x - 11*x^2 - 2*x^3 + 10*x^4). - _Colin Barker_, Jun 26 2018
%e Some solutions for n=4:
%e ..1..1..0..0....0..1..0..1....1..0..1..1....1..0..1..1....0..1..1..0
%e ..0..1..1..1....0..1..1..0....1..0..1..0....1..0..1..0....1..1..0..0
%e ..0..1..1..0....1..1..0..0....1..1..0..0....1..1..0..0....1..1..0..1
%e ..1..1..0..0....0..1..0..1....1..1..0..1....0..1..0..1....1..1..1..1
%Y Cf. A208028.
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 22 2012
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