### Episodes

Episode | Title | First Broadcast | Repeated | Comments |
---|---|---|---|---|

01 | One | 20050823 | 20070730 | |

02 | Two | 20050830 | 20070731 | is the basis of all even numbers but it's the idea of doubling that has established two as one of the most important tools in maths.|Its power can never be underestimated, from the growth of computer speed to its role in some of the latest theories in the expansion of our universe. |

03 | Six | 20050906 | 20070801 | The number six is a rare perfect number, once revered by ancient civilisations.|But how is it that everyone is linked by just six social ties? The number six is emerging as the key to understanding the nature of social networks, and is offering new insights into helping us understand all sorts of other connections from electric power grids to nerve cell groupings in our brains. |

04 | G: Newton's Gravitational Constant | 20050913 | 20070802 | Ever since Newton included G in his equations that define the strength of gravity there has been an ever greater desire to measure this tiny number with increasing accuracy.|But what does the value of G mean for the universe? If G was different, it would mean that stars would either burn too quickly or not form at all.|So is G perfectly tuned for life? |

05 LAST | 1729 | 20050920 | 20070803 | is the first of the Ramanujan numbers or taxicab numbers.|Its the smallest number that can be expressed as the sum of two cubed numbers in two different ways.|Mathematicians are competing, to seek more of them (with higher powers) as their properties hold the key to securing financial transactions over the internet. |