Err.. I don't think what you are asking for makes sense??
A specific page is already a "unique page"... so I don't understand how you could do something like "unique pages/visit for a given page"?? That would just be 1 divided by the number of visits that hit the page.... which doesn't sound useful at all.
However, what I think you are asking for, is more like an average "unique pages in a visit"
So if you had:
Visit 1:
- Page A
- Page B
- Page C
- Page A
(this would be 3 unique pages in this visit)
Visit 2:
(this would be 2 unique pages in this visit)
So (3 pages + 2 pages)/2 visits = 2.5 average, right?
I don't think this is possible in workspace... since you can't stack metrics to get an approximate distinct count per visit....
However, you might be able to create some custom code to support something like this....
Now, this would require figuring out a way to track what pages a user has visited on the front end (so that you only count each unique page once)... this would be the biggest challenge....
But, if you could get that logic working... you could increment a custom event on each "new" page, and then divide that by visits?
So:
Visit 1:
- Page A
- Page B
- Page C
- Page A
- eventX not sent, since this page has already been seen in the visit
Otherwise, I think what you are looking for would have to be done outside of Adobe in SQL....