The primes are the building blocks of our number system, but there's no general formula that will give you all of them. If you want them, you have to hunt them down one by one. Abigail Kirk investigates a method that does just that.
It has often been observed that mathematics is astonishingly effective as a tool for understanding the universe. But, asks Phil Wilson, why should this be? Is mathematics a universal truth, and how would we tell?
Marcus du Sautoy begins a two part exploration of the greatest unsolved problem of mathematics: The Riemann Hypothesis. In the first part, we find out how the German mathematician Gauss, aged only 15, discovered the dice that Nature used to chose the primes.