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