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%I #8 Aug 05 2018 15:06:12
%S 0,8,50,313,1980,12494,78880,497940,3143384,19843336,125265720,
%T 790768832,4991910856,31512587760,198930468440,1255794385648,
%U 7927491165000,50044112904464,315914982635800,1994286049109040,12589389751704584
%N Number of n X 3 arrays of occupancy after each element moves to some horizontal or antidiagonal neighbor, without consecutive moves in the same direction.
%C Column 3 of A221483.
%H R. H. Hardin, <a href="/A221478/b221478.txt">Table of n, a(n) for n = 1..66</a>
%F Empirical: a(n) = 8*a(n-1) - 7*a(n-2) - 24*a(n-3) + 6*a(n-4) for n>6.
%F Empirical g.f.: x^2*(8 - 14*x - 31*x^2 + 18*x^3 - 3*x^4) / (1 - 8*x + 7*x^2 + 24*x^3 - 6*x^4). - _Colin Barker_, Aug 05 2018
%e Some solutions for n=3:
%e ..1..2..0....1..2..0....0..3..0....0..2..0....1..2..0....0..1..1....0..3..0
%e ..0..2..1....1..2..1....2..0..1....1..3..1....0..2..2....1..3..1....1..1..0
%e ..0..2..1....0..2..0....0..3..0....0..1..1....0..2..0....0..2..0....1..2..1
%Y Cf. A221483.
%K nonn
%O 1,2
%A _R. H. Hardin_, Jan 17 2013
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