Strip of LEDs in a slow shutter
More from Chalkdust
The beautiful soaisu partition
Kenichi Takemura uncovers symmetries hidden in plain sight
Issue 21
Sudoku, potatoes and crossnumber's biggest secrets finally revealed in our spring 2025 issue. Plus all your favourite columns!
On the cover: flexahedron
Connie Bambridge-Sutton invites you to make a flexible 3D shape
Deal or no deal?
Mike Fletcher explores the optimal strategy for winning the popular television game show
2018 Fields medal winners
Introducing the work that has won mathematics' most famous award
Do you have too many or too few friends?
Do we have a natural limitation on the number of friends that we have?