I got partway through a graduate degree in math and I'm now doing something "completely different," but it bothers me that my skills are fading away. I don't have a lot of time, but I would like to devote 15 - 30 minutes a day to working on a problem, or some problems.
I'm curious where you'd look for problems if you were in a similar situation...
Here are some ideas to get started:
- Martin Gardner books
- Project Euler (but do the problems without computers)
- Measurement by Paul Lockhart
I wonder about textbooks. It's hard to push oneself through textbooks outside of a class, peers, deadlines. Maybe there are some which would be friendlier than others in this regard...?
The 15 - 30 minutes thing is a bit arbitrary. I'm just saying I can't count on having lots of time to spend. I started reading Munkres's Topology again, and Gleason's analysis book, intending to take my time, do most of the exercises, etc..
I suppose there aren't any specific skills I'm most interested in maintaining, but I was just looking to see if you had some ideas for ways to keep my head in the game.