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%I #5 Mar 31 2012 12:37:14
%S 8,64,168,558,1586,3726,9450,21318,47518,104470,220531,464202,957412,
%T 1949906,3940218,7868976,15610980,30742563,60142488,117047084,
%U 226575095,436635184,837955970,1601924662,3051891570,5795441060,10972726928
%N Number of 4Xn 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 0 1 and 1 0 1 vertically
%C Row 4 of A207024
%H R. H. Hardin, <a href="/A207027/b207027.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 4*a(n-1) -11*a(n-3) -13*a(n-4) +39*a(n-5) +29*a(n-6) -35*a(n-7) -84*a(n-8) +25*a(n-9) +53*a(n-10) +48*a(n-11) -15*a(n-12) +6*a(n-13) -69*a(n-14) -25*a(n-15) +a(n-16) +54*a(n-17) +2*a(n-18) +16*a(n-19) -12*a(n-20) -6*a(n-21) -15*a(n-22) +6*a(n-23) +3*a(n-25) +a(n-27) -a(n-28)
%e Some solutions for n=4
%e ..1..0..1..0....1..0..1..0....1..1..0..1....1..0..1..0....0..0..1..0
%e ..1..0..1..0....0..0..1..0....1..0..0..1....0..1..0..0....0..0..1..0
%e ..1..0..1..0....0..0..1..0....1..0..0..1....0..1..0..0....0..0..1..0
%e ..1..0..1..0....0..0..1..0....1..0..0..1....0..1..0..0....0..0..1..0
%K nonn
%O 1,1
%A _R. H. Hardin_ Feb 14 2012
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