Melvyn Bragg and his guests, including Vicky Neale, Whitehead Lecturer here in Oxford, discuss Euler's number, also known as e. First discovered in the seventeenth century by the Swiss mathematician Jacob Bernoulli when he was studying compound interest, e is now recognised as one of the most important and interesting numbers in mathematics. Roughly equal to 2.718, e is useful in studying many everyday situations, from personal savings to epidemics.

On 19 September 1994 Andrew Wiles finally proved Fermat’s Last Theorem, correcting the error in his original paper. It remains one of the great achievements in the history of mathematics and a compelling human story as captured in Simon Singh’s film.