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%I #5 Mar 31 2012 12:37:19
%S 9,81,387,1849,10535,60025,327075,1782225,9840285,54331641,298827711,
%T 1643572681,9050656627,49839223009,274344889595,1510158343225,
%U 8313840821405,45770001214609,251966391900979,1387088943911449
%N Number of 4Xn 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 0 1 and 1 0 0 vertically
%C Row 4 of A207741
%H R. H. Hardin, <a href="/A207742/b207742.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 4*a(n-1) +32*a(n-3) +132*a(n-4) -238*a(n-5) -136*a(n-6) -1068*a(n-7) -3958*a(n-8) +5414*a(n-9) +7248*a(n-10) +3912*a(n-11) +23868*a(n-12) -23346*a(n-13) -29268*a(n-14) -4140*a(n-15) -61497*a(n-16) +37350*a(n-17) +24948*a(n-18) -5400*a(n-19) +52920*a(n-20) -33264*a(n-21) -2592*a(n-22) -11664*a(n-24) +7776*a(n-25)
%e Some solutions for n=4
%e ..1..1..0..1....0..1..1..0....1..0..0..1....0..1..1..0....0..0..1..1
%e ..0..1..1..1....0..1..1..1....0..1..1..0....0..0..1..1....0..1..1..0
%e ..1..0..0..1....0..0..1..1....1..0..1..1....0..1..1..1....0..1..1..1
%e ..0..1..1..1....0..1..1..0....1..1..1..1....0..0..1..1....0..0..1..1
%K nonn
%O 1,1
%A _R. H. Hardin_ Feb 19 2012
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