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