In today's Sudoku, the clues between cells represent the least common multiple of the numbers contained in those cells. For example, if the clue is 72, then we know the numbers must be (8,9) in some order, but if the clue is 6, then the numbers could be (1,6),(2,6),(3,6), or (2,3).
Here's a second one that takes a little more work to solve.
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