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%I
%S 9,81,279,961,4743,23409,100215,429025,1942075,8791225,38933415,
%T 172423161,770225067,3440643649,15317395695,68191488225,303989603715,
%U 1355149763881,6037892299063,26901929503849,119887169037291
%N Number of 4 X n 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 0 0 and 1 0 1 vertically.
%C Row 4 of A208039.
%H R. H. Hardin, <a href="/A208040/b208040.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 2*a(n-1) +24*a(n-3) +117*a(n-4) +10*a(n-5) +88*a(n-6) -540*a(n-7) -2784*a(n-8) -648*a(n-9) +880*a(n-10) +2080*a(n-11) +11700*a(n-12) +4200*a(n-13) +2000*a(n-15) -10000*a(n-16).
%e Some solutions for n=4
%e ..1..1..0..1....1..0..0..1....1..0..0..1....0..1..1..0....0..1..1..0
%e ..0..1..1..1....1..0..1..1....1..0..1..1....0..1..1..1....1..0..0..1
%e ..0..0..1..1....0..1..1..1....0..1..1..0....1..0..0..1....1..0..0..1
%e ..1..0..0..1....0..0..1..1....0..1..1..0....1..0..0..1....1..1..1..1
%Y Cf. A208039.
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 22 2012
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