No, it is not that easy!
The solution here refers only to a 'small' square, e.g. 9 Cells = 1 Dropdown
In essence for a 'real' working solution you would need 81 ! Dropdowns, namely 1 for each of the 81 Cells of the 'big' square. This is because you have to eliminate numbers also if the are already used in their row and column of the big square. Working that out will be a real challenge.
@ExcellsFun
Sorry for the typo (copy/paste) from a german Excel for the named-range formula.
In english XL it should read:
=OFFSET($F$6,COUNTIF($F$6:$F$14,0),,9-COUNTIF($F$6:$F$14,0))
Perfect Squares - I just changed row and column height
Q1: Perfect Squares - I just changed row and column height.
Q2: I do not understand your question - can you restate it? If you are asking how to split a cell, there is no direct way to do it (like there is in a Word Table) and the indirect way is a hassle.
BTW, I have no idea how to play Sudoku, I just took this exercise as a logic challenge...
You are right. I have been teaching Excel for many years and the Mixed Cell References almost always make Smart people Crazy. :) If I did not know Excl I would use the online one too!