harmonic series
What is 11+11+11+...? How infinite sums challenge our notion of arithmetic. 
Usain Bolt, the "fastest man on the planet", aims to get his 100 metre world record of 9.58 seconds down to 9.40 seconds. What has mathematics got to say about this quest? 
Leonhard Euler was one of the most prolific mathematicians of all time. This year marks the 300th anniversary of his birth. Robin Wilson starts off a four part series on Euler with a look at his life and work.


Skot McDonald talks to Plus about how he uses mathematics to understand music, and how he managed to combine his passions for music and computing to create a successful career.

Infinite series occupy a central and important place in mathematics. C. J. Sangwin shows us how eighteenthcentury mathematician Leonhard Euler solved one of the foremost infinite series problems of his day.

The harmonic series is far less widely known than the arithmetic and geometric series. However, it is linked to a good deal of fascinating mathematics, some challenging Olympiad problems, several surprising applications, and even a famous unsolved problem. John Webb applies some divergent thinking, taking in the weather, traffic flow and card shuffling along the way.
