A221406 - OEIS

%I #4 Jan 15 2013 07:33:16

%S 0,120,0,47156,0,18852560,0,7505597654,0,2984164922226,0,

%T 1185951960926210,0,471249297474390114,0,187247029623260170674,0,

%U 74400007192624944055794,0,29561675588644660921885852,0

%N Number of nX5 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 5 of A221408

%H R. H. Hardin, <a href="/A221406/b221406.txt">Table of n, a(n) for n = 1..28</a>

%e Some solutions for n=4

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

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

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

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

%K nonn

%O 1,2

%A _R. H. Hardin_ Jan 15 2013