Some solutions for 4X4
..2..3..3..2....3..0..3..1....2..3..3..2....1..1..1..1....2..2..2..1
..2..2..1..3....1..1..1..0....2..0..1..1....2..1..2..1....3..2..3..3
..2..3..3..2....3..0..3..1....2..3..3..2....0..2..0..2....2..2..2..1
..3..1..2..2....1..1..1..0....2..0..1..1....2..1..2..1....3..2..3..3
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