cant solve it - tried several times now - really hard
Ok. This one's really hard. I have devised some convoluted path, though :
center 3x3 square (start with the 4)
top middle 3x3 square
right middle 3x3 square
We seem stuck... But we're not ! The 8th cell of the first col has only one possibility, and after that we can complete the first row. Then :
top right 3x3
3 2 6 9 1 7 4 5
The hardest puzzle so far here....
Nice to use the ol' noggin' a bit on that one.
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