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%I #4 Feb 28 2017 10:58:06
%S 0,6,72,600,4607,31669,208949,1324269,8152245,49070731,289979290,
%T 1687730558,9698213032,55123714128,310376329220,1733254750248,
%U 9609161226263,52931141892017,289892095063747,1579473182908079
%N Number of nX3 0..1 arrays with no 1 equal to more than one of its horizontal and vertical neighbors, with the exception of exactly two elements.
%C Column 3 of A283100.
%H R. H. Hardin, <a href="/A283095/b283095.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 6*a(n-1) +18*a(n-2) -52*a(n-3) -381*a(n-4) -543*a(n-5) +1654*a(n-6) +8943*a(n-7) +19026*a(n-8) +20615*a(n-9) +3639*a(n-10) -22728*a(n-11) -33125*a(n-12) -16047*a(n-13) +8640*a(n-14) +16878*a(n-15) +9570*a(n-16) +336*a(n-17) -3439*a(n-18) -2340*a(n-19) -477*a(n-20) +210*a(n-21) +216*a(n-22) +51*a(n-23) -13*a(n-24) -6*a(n-25) -3*a(n-26) +a(n-27)
%e Some solutions for n=4
%e ..1..0..1. .1..1..1. .1..0..1. .1..1..0. .0..0..1. .0..1..0. .0..0..1
%e ..0..0..1. .0..0..0. .0..1..0. .1..0..0. .1..1..1. .1..0..1. .0..0..0
%e ..0..1..1. .1..1..0. .1..1..1. .1..0..1. .0..0..1. .0..0..1. .0..1..1
%e ..0..0..0. .1..0..0. .0..0..1. .0..1..0. .0..0..0. .0..1..1. .1..1..0
%Y Cf. A283100.
%K nonn
%O 1,2
%A _R. H. Hardin_, Feb 28 2017