There is a relation between rectilinear-adjacent squares such that there is a unique rectilinear path from the top-left corner of the grid down to the bottom-right corner of the grid. Each square can participate in the path no more than once. What is the relation and the path it induces?

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• Follow the path of relation through the grid #1
• Follow the path of relation through the grid #2
• Follow the path of relation through the grid #3
• Follow the path of relation through the grid #4
• Follow the path of relation through the grid #5
• Follow the path of relation through the grid #6
• Follow the path of relation through the grid #7