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%I #5 Mar 31 2012 12:36:29
%S 1,9,18,83,245,914,3155,11287,39850,141325,501819,1782870,6328399,
%T 22463277,79770690,283288919,1005900951,3571642082,12682562591,
%U 45035370321,159915993486,567839908711,2016337387209,7159825934978
%N Number of nX3 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 3,3,1,1,0 for x=0,1,2,3,4
%C Every 0 is next to 0 3'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 0's
%C Column 3 of A197350
%H R. H. Hardin, <a href="/A197345/b197345.txt">Table of n, a(n) for n = 1..200</a>
%F Empirical: a(n) = a(n-1) +2*a(n-2) +8*a(n-3) +52*a(n-4) +40*a(n-5) +33*a(n-6) -34*a(n-7) -471*a(n-8) -603*a(n-9) -944*a(n-10) -786*a(n-11) +1306*a(n-12) +1460*a(n-13) +1840*a(n-14) +2248*a(n-15) -1768*a(n-16) -1536*a(n-17) -192*a(n-18)
%e Some solutions for n=4
%e ..1..3..1....0..0..1....1..3..1....0..1..2....1..3..1....1..0..0....0..0..1
%e ..2..1..2....1..1..3....0..1..1....1..3..1....2..1..2....3..1..0....0..1..3
%e ..2..1..0....3..1..1....0..1..3....1..3..1....0..1..0....1..1..0....0..2..1
%e ..1..3..1....1..0..0....0..2..1....0..1..0....1..3..1....1..3..1....0..0..0
%K nonn
%O 1,2
%A _R. H. Hardin_ Oct 13 2011
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