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%I #9 Oct 06 2018 06:15:17
%S 12,26,84,252,774,2360,7212,22024,67272,205466,627562,1916768,5854418,
%T 17881234,54614930,166811210,509494028,1556155380,4752989126,
%U 14517127208,44339883148,135427981664,413639750856,1263386202642,3858779756370
%N Number of n X 3 0..2 arrays with no element x(i,j) adjacent to value 2-x(i,j) horizontally, vertically or antidiagonally.
%H R. H. Hardin, <a href="/A232936/b232936.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = a(n-1) + 5*a(n-2) + 4*a(n-3) - a(n-5) for n>6.
%F Empirical g.f.: 2*x*(6 + 7*x - x^2 - 5*x^3 - x^4 + x^5) / ((1 + x)*(1 - 2*x - 3*x^2 - x^3 + x^4)). - _Colin Barker_, Oct 06 2018
%e Some solutions for n=5:
%e ..0..0..1....2..2..2....2..1..2....0..0..0....1..2..1....2..2..1....2..2..2
%e ..0..0..0....2..2..2....2..2..1....0..0..0....2..2..2....1..2..2....2..2..1
%e ..0..0..0....1..2..1....2..2..2....0..1..0....2..2..2....2..1..2....1..2..2
%e ..0..0..0....2..2..2....1..2..2....0..0..1....2..2..2....2..2..1....2..2..2
%e ..0..1..0....1..2..2....2..1..2....0..0..0....1..2..2....2..2..2....2..2..2
%Y Column 3 of A232941.
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 02 2013
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