If you want real maths and not just calculating, you'll need to do lots and lots of exercises. It's best if someone more experienced can grade them (it's hard t

If you want real maths and not just calculating, you'll need to do lots and lots of exercises. It's best if someone more experienced can grade them (it's hard to judge your own proofs), but looking at solutions helps too. You can get books for that (I don't know about ebooks), just ask around and have a look inside (Is there a university with a library nearby? You can try there.), different people need different books. I like the math part of The Art of Computer Programming (in the first book) by D. Knuth. It has exercises with solutions and, as the name says, is orientated towards maths useful for programming. Plus, it's a good read. The whole series came highly recommended, but I'm still in the first part, so I can't judge it yet. ^^