%I #5 Jan 11 2013 21:02:38
%S 0,18,370,6893,122690,2152076,37541550,653557217,11369057766,
%T 197715942522,3438053202520,59781409121813,1039472974649122,
%U 18074147498877660,314268989617804842,5464430347020252629
%N Number of nX3 arrays of occupancy after each element moves to some horizontal, diagonal or antidiagonal neighbor, without 2-loops
%C Column 3 of A221351
%H R. H. Hardin, <a href="/A221348/b221348.txt">Table of n, a(n) for n = 1..22</a>
%F Empirical: a(n) = 26*a(n-1) -162*a(n-2) +198*a(n-3) +305*a(n-4) -794*a(n-5) +668*a(n-6) -244*a(n-7) +72*a(n-8)
%e Some solutions for n=3
%e ..1..3..1....1..1..0....0..1..1....0..2..1....1..1..0....1..1..0....0..3..1
%e ..0..1..1....0..2..1....1..4..0....1..4..1....0..4..2....1..2..1....1..3..1
%e ..0..2..0....0..3..1....1..1..0....0..0..0....0..1..0....0..3..0....0..0..0
%K nonn
%O 1,2
%A _R. H. Hardin_ Jan 11 2013