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Was vaccinating vulnerable people first a good choice? Hindsight allows us to assess this question.

A game you're almost certain to lose...

What are the challenges of communicating from the frontiers of mathematical research, and why should we be doing it?

Celebrate Pi Day with the stars of our podcast,

*Maths on the move*!Maths meets politics as early career mathematicians present their work at the Houses of Parliament.

There are 2 things:

1. Choosing the rotors: Say choosing 3 from 5 rotors. That will be 5*4*3 or 5C3.

2. Positioning the rotors: Once we have chosen the rotors, they can be permuted. 3 rotors would be 3! i.e. 6 different ways.