I need thousands of cells with data validation... (Can a formula be used to return a list for data validation?)

I need to have thousands of cells controlled with data validation depending on the result of a formula, which is a slightly different formula for each cell (yea autofill). These formulas per se are already working well. However, I don’t know how to use these results to create a list for data validation.

Essentially, if the output of the formula is TRUE I need a certain list from data validation in that cell, and I need a different list if the output of the formula is FALSE.

I’ve noticed that in a data validation list, I can have an if statement which will return a range of cells.

However, I would at the very least need to know:

How do you apply data validation to thousands of cells at once?
How would I make sure each cell uses a different autofilled formula?

Also, is there a way to make a formula simply return a list used by data validation? [ ie, "=listsomehow(…) ) ] That would be the ideal solution - an almost immediate one.

I can use Macros. The problem is, none of the group of end-users are programmers, and so I would be the only one capable of maintaining it; we’ve discussed this. (They know about formulas, though.) I am very peripheral to that group, so I’d rather avoid this fate.

https://forum.openoffice.org/en/forum/download/file.php?id=333