## Fibonacci number

Does the famous Fibonacci sequence always appear in sunflower seed heads?

Anything involving bunny rabbits has to be good.

*The Da Vinci Code*, talks about the "divine proportion" as having a "fundamental role in nature". Brown's ideas are not completely without foundation, as the proportion crops up in the mathematics used to describe the formation of natural structures like snail's shells and plants, and even in Alan Turing's work on animal coats. But Dan Brown does not talk about mathematics, he talks about a number. What is so special about this number?

**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.

**Golden Ratio**, and ever since people have been fascinated by its extraordinary properties. Find out if beauty is in the eye of the beholder, and how the Golden Ratio crosses from mathematics to the arts.

**Keith Moffatt**tells us about three of the posters from the series.

**Kevin Jones**investigates the links between music and mathematics, throwing in limericks, Fibonacci and Scott Joplin along the way.

*Plus*is proud to present an extended version of his winning entry for the THES/OUP 1999 Science Writing Prize.

**Eugen Jost**is a Swiss artist whose work is strongly influenced by mathematics. He sent us this Postcard from Italy, telling us about his work and the important roles that nature and numbers play in it.