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