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A208035 Number of n X 4 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 0 0 and 1 0 1 vertically.

%I A208035 #11 Jun 27 2018 05:50:34
%S A208035 9,81,289,961,3249,11025,37249,126025,426409,1442401,4879681,16507969,
%T A208035 55845729,188925025,639128961,2162157001,7314525625,24744863025,
%U A208035 83711270241,283193201281,958035736849,3241011678961,10964263980289
%N A208035 Number of n X 4 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 0 0 and 1 0 1 vertically.
%C A208035 Column 4 of A208039.
%H A208035 R. H. Hardin, <a href="/A208035/b208035.txt">Table of n, a(n) for n = 1..210</a>
%F A208035 Empirical: a(n) = 2*a(n-1) + 3*a(n-2) + 6*a(n-3) - a(n-4) - a(n-6) for n>7.
%F A208035 Empirical g.f.: x*(9 + 63*x + 100*x^2 + 86*x^3 - 17*x^4 - 9*x^5 - 16*x^6) / ((1 + x + x^2 - x^3)*(1 - 3*x - x^2 - x^3)). - _Colin Barker_, Jun 27 2018
%e A208035 Some solutions for n=4:
%e A208035 ..0..1..1..0....1..0..1..1....0..0..1..1....1..0..0..1....0..1..1..1
%e A208035 ..0..1..1..1....0..0..1..1....1..1..1..1....1..1..0..1....0..1..1..1
%e A208035 ..1..0..0..1....0..1..1..0....0..1..1..1....0..1..1..0....1..0..0..1
%e A208035 ..1..0..0..1....1..1..1..0....0..1..1..0....0..1..1..0....1..0..0..1
%Y A208035 Cf. A208039.
%K A208035 nonn
%O A208035 1,1
%A A208035 _R. H. Hardin_, Feb 22 2012