Crossnumber enthusiasts might have noticed that 4 Down doesn’t actually quite work
Issue 2 crossnumber mistake
More from Chalkdust
Things to make
Platonic shapes from tube maps, flexagons, and more mathematical craft
What’s hot and what’s not
Optimal Pac-Man
Ghostbusting with graph theory
Reinventing 2D
What a difference a matrix makes
Your social networks
How similar are you to your friends?
Art meets maths