Probably next week I'll use ¡­

Probably next week I'll use some time to give a proof of theorem 15.15 which says that the alternating groups on n letters are simple if n is not 4. This is a most important theorem, in fact implying Abels theorem on the quintic equations, and I think it should be part of the course. I also prefer to do it a little differently than as in exercise 39 that book proposes, so I have written up a small note which you find on the web-side of the course.

Geir