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%I #6 Dec 18 2015 18:17:58
%S 1,7,258,34799,22100882,64449537503,847220834970347,
%T 50681890300309193984,13775254400039658772386790,
%U 17006093281906665293267116254138
%N Number of n X n 0..2 arrays with every 1 immediately preceded by 0 to the left or above, and every 2 immediately preceded by 0 1 to the left or above
%C Diagonal of A203975
%e Some solutions for n=4
%e ..0..0..0..0....0..0..1..0....0..0..0..0....0..0..1..0....0..0..1..2
%e ..1..1..0..1....1..1..0..0....0..1..1..1....1..1..0..0....0..0..0..0
%e ..0..0..0..1....0..0..1..2....1..2..0..0....0..1..0..0....0..1..0..1
%e ..1..0..1..0....0..0..0..0....2..0..1..2....0..1..2..1....0..0..0..1
%K nonn
%O 1,2
%A _R. H. Hardin_ Jan 08 2012