This month’s round up of mathematical blog posts from all over the internet

Think outside outside the box in our latest issue. No more tennis puns, primes mod 4, plus all your favourite regulars.

Biography of Sir Christopher Zeeman

Get into the ChristMATHS spirit with the maths behind the popular Christmas carol!

Maths and Decision Theory to be the best at playing Guess Who?

The joy of Jacobians | Fields Medallist Artur Avila | Fractograms | Nash's legacy | The perils of p-values