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%I
%S 9,81,177,575,1360,3106,8652,22114,53620,139806,360132,899952,2300016,
%T 5898082,14925674,37975776,96993892,246541258,627068300,1598281686,
%U 4067781864,10349972204,26357799164,67101532924,170780094962
%N Number of 4Xn 0..1 arrays avoiding 0 0 0 and 1 0 1 horizontally and 0 1 1 and 1 1 0 vertically
%C Row 4 of A207885
%H R. H. Hardin, <a href="/A207886/b207886.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = a(n-1) +a(n-2) +11*a(n-3) -2*a(n-4) -7*a(n-5) -31*a(n-6) +a(n-7) +6*a(n-8) +39*a(n-9) -4*a(n-10) +7*a(n-11) -24*a(n-12) -a(n-13) -6*a(n-14) +6*a(n-15) for n>17
%e Some solutions for n=4
%e ..0..0..1..0....1..1..0..0....0..0..1..1....0..0..1..0....1..1..0..0
%e ..1..0..0..1....1..1..0..0....1..0..0..1....0..0..1..0....0..0..1..0
%e ..0..0..1..0....1..1..1..0....0..0..1..1....1..1..1..0....0..1..0..0
%e ..1..0..0..1....1..1..0..0....1..0..0..1....0..0..1..0....1..0..0..1
%K nonn
%O 1,1
%A _R. H. Hardin_ Feb 21 2012
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