%I #5 Mar 31 2012 12:36:30
%S 0,8,0,27,27,154,272,1117,2321,7299,18275,54627,150925,405606,1155080,
%T 3116256,8868340,23994371,67730571,185335502,518769588,1425654497,
%U 3971507983,10973327639,30469831297,84329766549,233791763797
%N Number of nX3 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 0,3,1,1,1 for x=0,1,2,3,4
%C Every 0 is next to 0 0's, every 1 is next to 1 3's, every 2 is next to 2 1's, every 3 is next to 3 1's, every 4 is next to 4 1's
%C Column 3 of A197623
%H R. H. Hardin, <a href="/A197618/b197618.txt">Table of n, a(n) for n = 1..200</a>
%F Empirical: a(n) = 2*a(n-2) +2*a(n-3) +19*a(n-4) +31*a(n-5) +39*a(n-6) +74*a(n-7) +82*a(n-8) -66*a(n-9) -608*a(n-10) -91*a(n-11) -672*a(n-12) +57*a(n-13) -2166*a(n-14) +1531*a(n-15) +346*a(n-16) -20*a(n-17) +50*a(n-18) -12*a(n-19) -2*a(n-20)
%e Some solutions for n=4
%e ..2..1..0....0..2..1....2..1..2....1..3..1....0..1..2....2..1..0....1..3..1
%e ..1..3..1....1..1..3....1..3..1....0..1..2....1..3..1....1..3..1....2..1..0
%e ..1..3..1....3..1..1....1..3..1....2..1..2....1..3..1....1..3..1....2..1..2
%e ..2..1..2....1..2..0....2..1..0....1..3..1....0..1..0....0..1..2....1..3..1
%K nonn
%O 1,2
%A _R. H. Hardin_ Oct 16 2011
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