[math-fun] Most repeated longest substring

I'm having a little bit of trouble understanding the problem. It's a matter of how the quantifiers are nested, and how the counting is to be done. I would greatly appreciate it if Neil would go back to Al Aho and get a really clear description of the problem. My difficulties begin with the definition of f(X,Y). It is not clear that we are permitted to count multiple occurrences of the same substring; it seems equally probable to me that Aho wants to count only subsequences with distinct content. I have other similar hairsplitting problems, but let's start with that one. And ... remember the Al Aho. --ACW