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%I #10 Jul 08 2018 21:31:22
%S 9,81,126,196,504,1296,3312,8464,21712,55696,142544,364816,934992,
%T 2396304,6136272,15713296,40258384,103144336,264177872,676624144,
%U 1733335632,4440356496,11373699024,29133027856,74627823952,191168323984
%N Number of 4 X n 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 1 0 and 1 1 1 vertically.
%C Row 4 of A209224.
%H R. H. Hardin, <a href="/A209225/b209225.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = a(n-1) + 4*a(n-3) + 16*a(n-4) for n>7.
%F Empirical g.f.: x*(9 + 72*x + 45*x^2 + 34*x^3 - 160*x^4 - 1008*x^5 - 784*x^6) / ((1 + 4*x^2)*(1 - x - 4*x^2)). - _Colin Barker_, Jul 08 2018
%e Some solutions for n=4:
%e 1 1 0 1 0 0 1 1 0 1 1 0 0 1 1 1 0 1 1 1
%e 1 1 0 0 1 1 0 0 0 1 1 0 0 1 1 0 0 0 1 1
%e 0 0 1 1 1 1 0 0 1 0 0 1 1 0 0 1 1 1 0 0
%e 0 0 1 1 0 0 1 1 1 1 0 1 1 1 1 1 1 1 0 0
%Y Cf. A209224.
%K nonn
%O 1,1
%A _R. H. Hardin_, Mar 06 2012
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