What is the logical criterion used to place the four different symbols that fills the 36 cells of the 6 x 6 grid ?

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| O | # | x | @ | # | O |
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| @ | O | O | x | x | @ |
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| @ | x | O | # | # | @ |
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| # | @ | @ | x | O | # |
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| # | O | O | x | x | # |
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| x | @ | # | O | @ | x |
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(In reply to Is this as straightforward as it looks? by scott)

There seems to be a reflection in horizontal then vertical axes of o onto x and @ onto #

Posted by Lisa on 2005-06-03 13:00:10