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%I #12 Oct 14 2023 13:17:57
%S 0,44,464,6188,80160,1048566,13757056,180437354,2363318964,
%T 30930073844,404584067882,5290050421396
%N Number of 4 X n arrays of occupancy after each element stays put or moves to some horizontal, diagonal or antidiagonal neighbor, with every occupancy equal to zero or two.
%e Some solutions for n=3:
%e ..2..2..0....2..0..2....2..2..0....0..0..2....0..0..2....0..2..0....0..2..0
%e ..0..2..0....2..0..0....0..0..2....2..2..0....2..2..2....2..0..2....0..0..2
%e ..0..0..2....0..2..0....2..2..0....2..2..0....0..2..0....0..2..2....2..2..0
%e ..2..2..0....2..2..0....0..2..0....0..0..2....0..0..2....0..0..2....2..0..2
%Y Row 4 of A221728.
%K nonn,more
%O 1,2
%A _R. H. Hardin_, Jan 22 2013