Final lecture and problem set

I just put out the final lecture set -- welcome to everyone who has made it this far in this course!! Since attendance during the two discussion sessions was low, lecture 29 will be discussed on May 18 (no discussion session on May 14!) and the final one (#30) only on May 21.

There are also no further problem sets, the last one (#15) will be discussed this week during the usual slot (on May 12).