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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Starting from the top left, following the pattern:
go one down, go diagonally up and right, go one to the right, go
diagonally down and left, go one down, go diagonally up and to the
right, ...
With this pattern the sequence
O@#xO@#xO@#x etc is formed.
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Solution
