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%I #4 Jan 19 2013 20:49:47
%S 2,71,1930,48018,1200093,29961271,747830157,18664821555,465841969135,
%T 11626559958154,290177113520981,7242272238158273,180753392894785450,
%U 4511261939241006332,112592541470281392840,2810096262246752615123
%N Number of 3Xn arrays of occupancy after each element moves to some horizontal, vertical or antidiagonal neighbor, without move-in move-out left turns
%C Row 3 of A221551
%H R. H. Hardin, <a href="/A221553/b221553.txt">Table of n, a(n) for n = 1..85</a>
%e Some solutions for n=3
%e ..1..0..0....2..1..0....2..1..1....0..2..1....1..1..1....0..3..1....1..0..0
%e ..3..0..2....1..0..1....1..1..1....2..0..1....3..0..0....1..0..0....3..0..3
%e ..1..1..1....1..3..0....0..2..0....0..2..1....0..1..2....1..1..2....1..0..1
%K nonn
%O 1,1
%A _R. H. Hardin_ Jan 19 2013