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%I #5 Mar 31 2012 12:37:15
%S 8,64,216,720,2688,8799,27063,84502,257584,762900,2246895,6565968,
%T 18955015,54365475,155191828,440404000,1244062260,3502380028,
%U 9826626600,27487369521,76702016405,213558055578,593398011328,1645981275528
%N Number of 4Xn 0..1 arrays avoiding 0 0 1 and 0 1 0 horizontally and 0 0 1 and 1 0 1 vertically
%C Row 4 of A207068
%H R. H. Hardin, <a href="/A207071/b207071.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 7*a(n-1) -20*a(n-2) +60*a(n-3) -200*a(n-4) +406*a(n-5) -795*a(n-6) +1948*a(n-7) -2956*a(n-8) +4315*a(n-9) -9183*a(n-10) +10237*a(n-11) -11623*a(n-12) +25456*a(n-13) -18911*a(n-14) +17833*a(n-15) -49104*a(n-16) +18984*a(n-17) -18492*a(n-18) +71354*a(n-19) -5313*a(n-20) +14092*a(n-21) -75268*a(n-22) -12707*a(n-23) -8053*a(n-24) +56095*a(n-25) +16847*a(n-26) +4140*a(n-27) -28320*a(n-28) -9288*a(n-29) -828*a(n-30) +8208*a(n-31) +2376*a(n-32) -1296*a(n-34)
%e Some solutions for n=4
%e ..1..0..1..1....1..1..0..0....0..0..0..0....0..1..1..1....0..1..1..1
%e ..0..0..0..0....0..1..1..1....0..1..1..0....1..1..1..0....0..0..0..0
%e ..0..0..0..0....0..1..1..1....0..1..1..0....1..0..0..0....0..0..0..0
%e ..0..0..0..0....0..1..1..1....0..0..0..0....0..0..0..0....0..0..0..0
%K nonn
%O 1,1
%A _R. H. Hardin_ Feb 14 2012
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