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%I #7 Jan 15 2013 11:13:01
%S 0,38,144,89173,2294372,247200529,10874636860,776880319370,
%T 41186123651894,2584866896797503,146335664855961366
%N Number of 4 X n arrays of occupancy after each element moves to some horizontal, diagonal or antidiagonal neighbor, with no 2-loops and with no occupancy greater than 2.
%C Row 4 of A221400.
%e Some solutions for n=3
%e ..0..2..0....0..2..0....0..2..0....0..2..0....0..2..0....0..2..0....1..2..1
%e ..2..2..1....2..2..0....2..2..0....1..2..2....1..2..0....0..2..2....1..2..0
%e ..0..2..0....0..2..2....1..2..0....0..2..0....1..2..1....0..2..2....0..2..0
%e ..0..2..1....0..2..0....0..2..1....1..2..0....1..2..0....0..2..0....0..2..1
%K nonn
%O 1,2
%A _R. H. Hardin_, Jan 15 2013
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