Some solutions for n=4
..2..2..3..3....3..3..2..2....2..2..3..2....2..2..3..2....2..2..3..2
..2..1..3..2....3..1..2..0....2..1..1..0....2..1..1..2....2..1..1..2
..2..1..2..3....2..2..2..0....3..3..2..2....3..3..2..2....3..3..0..0
..2..0..2..2....2..0..0..0....2..1..2..3....2..2..0..2....2..1..3..0
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