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A208109 Number of 4 X n 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 1 1 and 1 1 0 vertically.

%I A208109 #9 Jun 28 2018 08:25:26
%S A208109 9,81,171,361,1805,9025,25555,72361,292941,1185921,3801699,12187081,
%T A208109 45351581,168766081,570110035,1925893225,6923341485,24888533121,
%U A208109 85943617731,296775442441,1051712556989,3727058052481,12988702493491
%N A208109 Number of 4 X n 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 1 1 and 1 1 0 vertically.
%C A208109 Row 4 of A208108.
%H A208109 R. H. Hardin, <a href="/A208109/b208109.txt">Table of n, a(n) for n = 1..210</a>
%F A208109 Empirical: a(n) = 2*a(n-1) + 8*a(n-3) + 61*a(n-4) - 66*a(n-5) - 48*a(n-6) - 252*a(n-8) + 216*a(n-9).
%F A208109 Empirical g.f.: x*(9 + 63*x + 9*x^2 - 53*x^3 - 114*x^4 - 300*x^5 - 36*x^6 - 36*x^7 + 216*x^8) / ((1 - 2*x - 7*x^2 + 6*x^3)*(1 + 7*x^2 - 12*x^4 - 36*x^6)). - _Colin Barker_, Jun 28 2018
%e A208109 Some solutions for n=8:
%e A208109 ..0..1..1..1..0..1..1..1....1..0..1..1..1..0..1..1....0..1..1..1..1..1..1..1
%e A208109 ..1..1..1..0..0..1..1..0....0..0..1..1..1..0..1..1....1..0..1..1..1..0..1..1
%e A208109 ..0..1..1..0..0..1..1..1....0..0..1..1..1..1..1..1....0..0..1..1..1..0..1..1
%e A208109 ..0..1..1..1..0..1..1..0....1..1..1..1..1..0..1..1....0..1..1..1..1..0..1..1
%Y A208109 Cf. A208108.
%K A208109 nonn
%O A208109 1,1
%A A208109 _R. H. Hardin_, Feb 23 2012