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%I #5 Mar 31 2012 12:36:25
%S 3,5,8,17,34,62,123,243,471,924,1817,3558,6978,13697,26865,52699,
%T 103398,202847,397944,780720,1531657,3004865,5895113,11565346,
%U 22689467,44513380,87328672,171325871,336115955,659409701,1293664016,2537976953,4979134498
%N Number of nX2 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 3,0,4,1,2 for x=0,1,2,3,4
%C Every 0 is next to 0 3's, every 1 is next to 1 0's, every 2 is next to 2 4's, every 3 is next to 3 1's, every 4 is next to 4 2's
%C Column 2 of A196146
%H R. H. Hardin, <a href="/A196140/b196140.txt">Table of n, a(n) for n = 1..200</a>
%F Empirical: a(n) = 2*a(n-1) +a(n-3) -2*a(n-4) -a(n-5) +a(n-6)
%e Some solutions for n=4
%e .1.0...0.1...1.0...0.0...0.1...1.0...1.0...1.0...0.0...1.1
%e .1.0...1.3...3.1...0.0...0.1...1.1...1.0...3.1...1.1...0.0
%e .1.1...3.1...1.1...0.0...1.1...0.1...1.0...1.3...1.1...0.0
%e .0.1...1.0...0.0...1.1...1.0...0.1...1.0...0.1...0.0...0.0
%K nonn
%O 1,1
%A _R. H. Hardin_ Sep 28 2011
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