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