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%I #6 Dec 18 2015 18:17:56
%S 1,85,4057,988589,722587629
%N Number of zero-sum n X n -2..2 arrays with every element unequal to at most two horizontal and vertical neighbors
%C Diagonal of A201803
%e Some solutions for n=3
%e ..2..0..0....0..0..0....0..0.-2...-2..0.-1....2.-1.-1...-1..1..2....0.-2.-2
%e .-2.-2.-2....1..0..0....0..0..0....0..0.-1....1.-1.-1....1..1.-2....1..1..1
%e ..2..1..1....1..0.-2....2..2.-2....2..2..0....1..0..0....2.-2.-2....0..1..0
%K nonn
%O 1,2
%A _R. H. Hardin_ Dec 05 2011
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