> directory cannot be directly accessed like a FTP
> directory (gives 403 forbidden error). Instead the
There is no magic here. What part of forbidden wasn't clear?
> only way to access these files (PDFs) is through the
> roundabout fashion (clicking through these links):
Either through the links or you guess the URLs: Number sequences: How to
mirror only files/URLs using a certain ID/number range -
<http://httrack.kauler.com/help/URL_number_sequences>

> I've tried some rules before, but they ended up
> downloading most/all of the site on
Filters do just that, they don't enable magic. If you want one file type: -*
+*.html +*.XXX