I graduated with an undergraduate mathematics degree this past May, but I had never taken a Discrete Mathematics course. I took the usual years' worth of Algebra and Analysis.
I am interested in a discrete mathematics text (with challenging problems) that covers all of the topics on the Math GRE Subject Test, i.e.,
Discrete mathematics: logic, set theory, combinatorics, graph theory and algorithms
and won't be boring for me to read, given my math background.
(I have heard that I would be bored in such a class, as I once spoke to a Discrete Math professor about taking her class, and she told me it would be a waste of time.)
What you probably want is the MIT Course Notes for CS Math (Discrete Mathematics). It is used at Harvard and MIT, as well as my local university and it is Creative Commons Licensed (The specific license for the course notes are Attribution+Noncommercial+ShareAlike).
The "book" is: Mathematics for Computer Science
BY:
Eric Lehman, Google
F Thomson Leighton, MIT
Alebert R Meyer, MIT
With your math background though you should be fine without perusing it for the Math GRE as others have pointed out.
Creative Commmons License for Reference