I do not think that using math or other predictions you can win in gambling, and especially in roulette. There everything is designed for pleasure, not profit.
This is different from games like Blackjack where the probability changes when the card is shared.
But some people believe that it is possible to exploit the way the roulette wheel, and the wager fabric, is laid to benefit themselves.
The idea is that you can make a bet on the layout in a way that you believe will win.
Thats what Pelayos brothers did. They realized some roulette wheels had tiny imperfections and created a system to win long-term.
A film about the story was shot some years ago:
http://www.imdb.com/title/tt1843202/But after that, casinos learned the lesson and I dont think nowadays you can find imperfections.