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%I #9 Mar 01 2018 09:11:44
%S 3,6,14,36,83,192,468,1112,2624,6267,14941,35493,84487,201229,478826,
%T 1139543,2712764,6456865,15367802,36579318,87067091,207234557,
%U 493260338,1174064036,2794503372,6651474771,15831865426,37683024434,89693152856
%N Number of n X 2 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 3,0,2,1,4 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 2's, every 3 is next to 3 1's, every 4 is next to 4 4's.
%C Column 2 of A196485.
%H R. H. Hardin, <a href="/A196479/b196479.txt">Table of n, a(n) for n = 1..200</a>
%F Empirical: a(n) = 2*a(n-1) + 4*a(n-3) - 3*a(n-4) - 3*a(n-5) - a(n-6) + a(n-7) -a(n-8).
%F Empirical g.f.: x*(3 + 2*x^2 - 4*x^3 - 4*x^4 - 3*x^5 + 3*x^6 - 3*x^7) / (1 - 2*x - 4*x^3 + 3*x^4 + 3*x^5 + x^6 - x^7 + x^8). - _Colin Barker_, Mar 01 2018
%e Some solutions for n=4:
%e ..0..0....0..0....2..2....0..0....1..1....2..2....1..0....0..0....0..0....1..1
%e ..0..0....1..1....2..2....2..2....0..0....2..2....1..0....1..1....0..0....0..0
%e ..0..0....2..2....0..0....2..2....2..2....0..0....1..0....3..1....2..2....0..0
%e ..0..0....2..2....0..0....1..0....2..2....1..1....1..0....1..0....2..2....0..0
%Y Cf. A196485.
%K nonn
%O 1,1
%A _R. H. Hardin_, Oct 03 2011
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