The revisions let you track differences between multiple versions of a post.
Added a reference to an as-yet non-existent page on Bass--Serre Theory.
Clarified how the examples fit together, I hope.
add the affine transformation example
changed a^2 b = ba^3 to ab = ba^2 for consistency (though perhaps we could remark how the different methods extend in different ways); also wikilinked Britton's lemma
Put the example into some context.
Another stub; my group theory is rusty, though, and the example may not be the best one
View a list of all articles.
Tricki