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%I #12 Jun 24 2018 14:43:01
%S 9,81,144,432,1098,3150,8244,23202,61560,171468,458640,1269144,
%T 3412944,9402156,25378560,69694632,188620632,516830904,1401394608,
%U 3833746488,10409369472,28443841344,77305743936,211065666624,574042728672
%N Number of 4 X n 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 0 1 and 1 1 1 vertically.
%C Row 4 of A207589.
%H R. H. Hardin, <a href="/A207591/b207591.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 8*a(n-2) + 2*a(n-3) - 10*a(n-4) + 2*a(n-6) for n>8.
%F Empirical g.f.: 9*x*(1 - x)*(1 + 10*x + 18*x^2 - 8*x^3 - 22*x^4 + 2*x^5 + 4*x^6) / (1 - 8*x^2 - 2*x^3 + 10*x^4 - 2*x^6). - _Colin Barker_, Jun 24 2018
%e Some solutions for n=4:
%e 0 1 1 0 0 1 0 0 1 0 1 1 1 0 1 1 0 1 1 0
%e 1 0 1 1 1 0 1 1 0 1 1 1 0 1 0 1 1 0 1 0
%e 0 1 0 0 1 1 1 0 1 1 0 0 1 0 1 0 1 1 0 0
%e 1 0 1 0 0 1 0 0 1 0 1 0 0 1 0 1 0 1 1 0
%Y Cf. A207589.
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 19 2012
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