Sage notebook on relations

I filled in for Al Doerr in his class this morning and he asked me to cover some material on relations. So I took that opportunity to figure out how to implement some relations in Sage. It went pretty well. One exception is that in squaring an adjacency matrix of a relation, I'd like to get a simple adjacency matrix with just 0's and 1's. The way I did the calculations, I got the numbers of different paths of length 2 connecting the vertices. That's fine except that the graphs of the squared relations become messy. If anyone knows how to fix this, I'd appreciate the help.

http://www.sagenb.org/home/pub/4715

Two Part Version of Applied Discrete Structures

Applied Discrete Structures is now available in either a single volume or in a two part version:
Part 1 - Fundamentals
Part 2 - Algebraic Structures
It broken according to how the two semesters of discrete math are taught at UMass Lowell. We did this for a few reasons. One is that many of our students only need to take the first semester. Also, the full version, whether as a pdf or a printed book, is quite large (484 pages).

Information on the one and two part versions (as free pdf's or printed copies from lulu.com) is available on our web site:
http://faculty.uml.edu/klevasseur/ads2