Some solutions for n=4
.....0........0........0........0........0........0........0........0
....1.1......1.1......1.1......1.0......1.0......1.1......1.2......1.1
...0.1.2....2.2.3....0.1.1....1.1.2....2.1.1....2.1.0....3.3.3....2.2.2
..3.3.2.2..0.2.2.2..2.1.3.2..1.1.0.0..2.1.1.1..3.3.2.3..1.3.2.2..2.1.2.3
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