In Response To 'Re: Re: Re: Collecting terms in an expression'
This was exactly what I was looking for. Thanks a lot.
By those "...", I meant counting from 1 to n. I wrote at first that I am working with "n" variables. So, I couldn't include explicitly all variables.
But you are right, I will attach a notebook of my question later on.
Btw, if you could please describe a bit what the "underline before the bracket" and ".." do, I would really appreciate it. I couldn't find any of these in Mathematica documentation. Actually, they were the only things I was missing for simplifying my expr.