%I #4 Jan 22 2013 07:14:49

%S 1,144,3112,95076,2627760,74531185,2098932856,59210733473,

%T 1669668324450,47086135048676,1327854674388881,37446255355092156,

%U 1056006037475086696,29779973215497145163,839812326958816104725,23683188619380401285537

%N Number of 3Xn arrays of occupancy after each element stays put or moves to some horizontal or antidiagonal neighbor, without consecutive moves in the same direction

%C Row 3 of A221693

%H R. H. Hardin, <a href="/A221695/b221695.txt">Table of n, a(n) for n = 1..69</a>

%e Some solutions for n=3

%e ..0..3..2....0..3..0....1..0..0....0..2..0....1..0..1....2..0..0....1..0..2

%e ..0..1..0....0..1..1....2..1..1....2..2..1....2..1..1....2..1..1....2..1..0

%e ..1..2..0....2..2..0....1..3..0....1..0..1....1..2..0....1..0..2....0..3..0

%K nonn

%O 1,2

%A _R. H. Hardin_ Jan 22 2013