OFFSET
1,2
COMMENTS
Diagonal of A229510.
EXAMPLE
Some solutions for n=3:
0 1 2 0 1 2 0 0 0 0 0 1 0 1 2 0 1 2 0 1 0
0 0 0 2 1 1 1 2 2 1 0 2 2 2 2 0 1 2 2 2 2
1 2 1 0 0 2 1 1 1 2 0 2 1 0 0 1 1 0 2 1 1
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Sep 25 2013
STATUS
approved