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%I #5 Dec 18 2015 18:18:25
%S 1,19,2899,4119299,53074198285,6137910765383119
%N Number of n X n arrays of occupancy after each element stays put or moves to some horizontal or vertical neighbor, with no occupancy greater than 2
%C Diagonal of A221303
%e Some solutions for n=3
%e ..1..0..2....1..2..0....1..1..1....0..1..2....2..1..0....0..0..2....0..2..1
%e ..2..1..1....0..2..1....0..1..1....1..1..1....0..0..2....1..2..2....2..1..1
%e ..0..0..2....2..1..0....0..2..2....1..1..1....2..1..1....0..2..0....0..2..0
%K nonn
%O 1,2
%A _R. H. Hardin_ Jan 09 2013