scattered formulated on Tuesday :

Out of curiosity, what is the motivation for this problem?
I don't really know, it is not a problem of mine.
The OP put the question from an italian Excel NG and its mathematical
aspect captured my interest in the very same way it happened to you.

I have some ideas about how to modify the code so that it will keep track of
the rows where each combination appears (and still run in a couple of
seconds), but the resulting code would be too long to easily post. Perhaps we
can continue this conversation via e-mail. Feel free to send me one (prefix
"re" to my nickname and add the usual gmail suffix)
Ok, I'll add some info to my worksheet containing the full solution
and I'll send you it by mail.

I didn't realize you could specify the variant subtype when redimensioning
the variable. That is useful to know. Thanks.

I am from the US, near Pittsburgh. Professionally I do math and computer
science (mostly math) which is why your post raised my interest.
I am living in Forlì, central-northen Italy, near Bologna, the oldest
(1088 AD) university in the western world.
I'm retired (nearly 80).

Bruno