Weirdonacci

Nora Koparan tells the story of the first female professor of mathematics

Pigs, popes and produce are among the topics of discussion in this issue's Dear Dirichlet advice column

How many did you spot?

This year's Chalkdust puzzle Christmas card

What happens if you play the prisoners' dilemma against yourself?

Favourite numbers for many are linked to birthdays or anniversaries, but here is our take on the question