Ask HN:Friend is math/algorithmic genius, wants to learn programming. Resources?

I have a friend, who has an uncanny talent for anything mathematical. He can write formulas and functions to solve the most obscure math problems, and he has the mind of an algorithmic thinker that I and probably many wish they had. Think project Euler, he's really good at those types of problems.

He doesn't actually know any code, but I feel like he would be able to accomplish so many things with it. I've talked to him about it, and he's really interested, but he doesn't know where to start. Due to financial issues, he occasionally does not have Internet, but he does have a decent and functional computer to work with. What books/tutorials/resources should I give him so that he can put his mathematical and problem-solving talent to good use?