%I #4 Oct 01 2012 06:03:02
%S 0,7,144,2389,37114,561573,8399702,124988061,1855434240,27513859347,
%T 407794083248,6042695120617,89531233299098,1326469665327327,
%U 19652162517014150,291151404103798147,4313455938625144092
%N Number of nX3 arrays of occupancy after each element moves to some horizontal or vertical neighbor but without 2-loops
%C Column 3 of A217346
%H R. H. Hardin, <a href="/A217341/b217341.txt">Table of n, a(n) for n = 1..53</a>
%F Empirical: a(n) = 23*a(n-1) -125*a(n-2) +13*a(n-3) +648*a(n-4) -208*a(n-5) -1279*a(n-6) +327*a(n-7) +1739*a(n-8) -1293*a(n-9) +138*a(n-10) +130*a(n-11) +8*a(n-12)
%e Some solutions for n=3
%e ..0..0..0....1..2..1....0..2..1....1..1..0....0..0..0....1..1..1....0..0..0
%e ..2..2..2....1..0..1....1..2..1....2..2..0....2..3..1....2..1..2....1..3..2
%e ..1..1..1....1..1..1....1..1..0....1..2..0....1..2..0....1..0..0....0..2..1
%K nonn
%O 1,2
%A _R. H. Hardin_ Oct 01 2012