Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).
%I #3 Jan 15 2013 07:33:45
%S 8,328,12668,492102,18852560,722442370,27665242848,1058237377670
%N Number of nX6 arrays of occupancy after each element stays put or moves to some horizontal or vertical neighbor, with every occupancy equal to zero or two
%C Column 6 of A221408
%e Some solutions for n=3
%e ..0..0..2..0..2..2....0..0..2..2..0..2....2..2..0..2..0..2....2..0..0..0..2..0
%e ..2..0..0..2..0..0....2..0..2..0..0..2....2..0..0..2..0..0....2..2..2..2..2..0
%e ..2..0..2..2..0..2....0..2..2..0..0..2....0..2..2..0..2..0....0..0..2..0..0..2
%K nonn
%O 1,1
%A _R. H. Hardin_ Jan 15 2013