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%I #5 Mar 31 2012 12:36:27
%S 2,10,34,104,386,1380,4800,16794,58875,206084,721260,2525126,8840855,
%T 30952194,108366098,379400544,1328316102,4650549495,16281977271,
%U 57004611828,199578061611,698740003512,2446349057586,8564879222176
%N Number of nX3 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 4,3,0,2,1 for x=0,1,2,3,4
%C Every 0 is next to 0 4's, every 1 is next to 1 3's, every 2 is next to 2 0's, every 3 is next to 3 2's, every 4 is next to 4 1's
%C Column 3 of A196974
%H R. H. Hardin, <a href="/A196969/b196969.txt">Table of n, a(n) for n = 1..200</a>
%F Empirical: a(n) = 2*a(n-1) +5*a(n-2) +2*a(n-3) -2*a(n-4) -11*a(n-5) +a(n-6) +36*a(n-7) +50*a(n-8) +20*a(n-9) -20*a(n-10) -49*a(n-11) -42*a(n-12) -20*a(n-13) +4*a(n-14) +9*a(n-15) +2*a(n-16)
%e Some solutions for n=4
%e ..0..2..0....0..0..0....2..0..0....0..0..2....0..0..2....0..2..0....0..0..2
%e ..2..3..2....2..3..2....0..2..2....0..0..0....2..2..0....0..2..2....2..2..0
%e ..0..0..0....0..2..0....2..3..0....2..2..0....0..3..2....0..0..0....0..2..0
%e ..0..0..0....0..2..0....0..2..0....0..2..0....0..2..0....0..0..2....0..2..0
%K nonn
%O 1,1
%A _R. H. Hardin_ Oct 08 2011
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