In issue 29 of Plus, we heard how a simple mathematical equation became the subject of a debate in the UK parliament. Chris Budd and Chris Sangwin continue the story of the mighty quadratic equation.
How does the uniform ball of cells that make up an embryo differentiate to create the dramatic patterns of a zebra or leopard? How come there are spotty animals with stripy tails, but no stripy animals with spotty tails? Lewis Dartnell solves these, and other, puzzles of animal patterning.
There are many different types of lottery around the world, but they all share a common aim: to make money. John Haigh explains why lotteries are the way they are.
  • Editorial trends - According to current trends, this editorial will never get written!
  • I've got your number - Soon the maths-phobic will have nowhere left to hide.
  • The Smith report: Making mathematics count
  • Quadratic equations in Parliament!
  • New look for Nrich - Our sister site Nrich unveils its new site design.
It isn't often that a mathematical equation makes the national press, far less popular radio, or most astonishingly of all, is the subject of a debate in the UK parliament. However, as Chris Budd and Chris Sangwin tell us, in 2003 the good old quadratic equation, which we all learned about in school, reached these dizzy pinnacles of fame.