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%I #9 Apr 27 2021 21:03:46
%S 0,6,480,50112,9854784,4032737280,3594819388032,7178082866740800,
%T 32598674667546519744,340101114114677727107520,
%U 8206049057729134245814363392
%N Number of defective 3-colorings of an n X n 0..2 array connected diagonally and antidiagonally with exactly one mistake, and colors introduced in row-major 0..2 order.
%C Diagonal of A229510.
%e Some solutions for n=3:
%e 0 1 2 0 1 2 0 0 0 0 0 1 0 1 2 0 1 2 0 1 0
%e 0 0 0 2 1 1 1 2 2 1 0 2 2 2 2 0 1 2 2 2 2
%e 1 2 1 0 0 2 1 1 1 2 0 2 1 0 0 1 1 0 2 1 1
%Y Cf. A229510.
%K nonn
%O 1,2
%A _R. H. Hardin_, Sep 25 2013