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%I #5 Mar 31 2012 12:36:57
%S 0,4,72,144,1840,10404,69920,490000,3317120,22524516,153723240,
%T 1044840976,7112904336,48420242116,329561076960,2243249071504,
%U 15269163209664,103931377966276,707427841294920,4815226903450896
%N Number of nX3 0..2 arrays with every element neighboring horizontally or vertically both a 0 and a 1
%C Column 3 of A203542
%H R. H. Hardin, <a href="/A203537/b203537.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 7*a(n-1) -8*a(n-3) -38*a(n-4) +218*a(n-5) +400*a(n-6) -2936*a(n-7) +609*a(n-8) -2791*a(n-9) +4072*a(n-10) +248*a(n-11) -588*a(n-12) +4916*a(n-13) -1912*a(n-14) +8920*a(n-15) -7799*a(n-16) +3393*a(n-17) -5960*a(n-18) -464*a(n-19) -238*a(n-20) +18*a(n-21) -56*a(n-22) -9*a(n-24) -a(n-25)
%e Some solutions for n=5
%e ..1..1..2....2..0..0....0..1..2....0..1..0....0..1..1....2..1..0....2..0..1
%e ..0..0..0....1..1..1....0..1..0....0..1..0....0..0..0....0..1..0....1..0..1
%e ..1..2..1....0..1..1....2..1..0....2..2..1....1..0..0....0..0..1....1..2..1
%e ..1..0..1....0..0..0....0..1..0....1..0..1....1..1..1....1..0..1....0..0..0
%e ..2..0..1....1..1..1....0..1..2....1..0..1....0..0..1....1..0..0....2..1..1
%K nonn
%O 1,2
%A _R. H. Hardin_ Jan 02 2012
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