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A172478
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The number of ways to dissect an n X n square into polyominoes of size n and then fill it to make it a Latin square, with the extra requirement that each number occurs within each polyomino exactly once.
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0
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OFFSET
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1,2
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COMMENTS
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a(n) is the number of completed n X n jigsaw sudoku puzzles.
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REFERENCES
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J. de Ruiter, On Jigsaw Sudoku Puzzles and Related Topics, Bachelor Thesis, Leiden Institute of Advanced Computer Science, 2010. [From Johan de Ruiter, Jun 15 2010]
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LINKS
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EXAMPLE
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A 2 X 2 square can be covered by two dominoes by either positioning them vertically or horizontally. Both of these coverings allow for two 2 X 2 Latin squares without violating the extra constraint.
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CROSSREFS
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Cf. A002860 (Number of Latin squares of order n), A172477 (Number of ways to dissect an n X n square into polyominoes of size n).
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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