5 through 15

So Oliver Willis said some glowing things about Bill Clinton, and then "Conservative since 63" followed up and said:

100 years from now he'll be as unknown as are the 5th to 15th Presidents -- go ahead, name them without looking them up.

I think we'll have to wait to see whether he's right, but it's an odd choice of example, considering that the list includes Andrew Jackson. And James K. Polk, who is mostly forgotten except to They Might Be Giants fans, but who was extremely important, if not really admirable (during his administration, the United States doubled in size through naked imperial aggression). That nobody can remember their numbers is hardly a demerit. Jackson's on the twenty!
( I attempt the puzzle )