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A105074
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Number of ways to fill in an n X n grid such that the digits of each row and each column form a square number.
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1
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OFFSET
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1,1
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COMMENTS
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Leading zeros are forbidden in the rows and columns.
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LINKS
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EXAMPLE
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The 1 X 1 crosssquare-puzzle is easy; the only solutions are 1, 4, and 9.
The 4 solutions for n=2 are [16/64], [36/64], [64/49], [81/16].
Or, writing them as 2 X 2 matrices,
16 36 64 81
64 64 49 16
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CROSSREFS
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KEYWORD
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nonn,base,more
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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