Question

1. I have as many books as you.
2. I have as many books as you do.
3. I have as many books as you have.
4. I have as many books as you have books.
5. I have as many books as you have them.
6. I have many books. You have many books.
=> I have as many books as you have.

[I have written down possible sentences. Which ones are used? Did #1 come from #6?]

Answer 1

1-3 are fine, but 4 and 5 aren't.

Yes, #1 comes from #6.

Answer 2

since "many" is vague and unspecified, #6 in no way implies #1. For example, #6 might be:

I have 100 books.
You have 1000 books.

We both have "many" books, but #1 is clearly false.

Still, in the context of these sentences, maybe #6 means #1, since we seem to be talking about equal amounts of books.