When Truchet met Chladni Stephen Muirhead meets neither, as he explores waves, tiles and percolation theory

Playing billiards with cue-bics Yuliya Nesterova misses all the pockets, but does manage to solve some cubics

Hiding in plain sight Axel Kerbec gets locked out while exchanging keys

On the cover: Harriss spiral Find out more about the spiral trees on the cover of Issue 09

Bells, braids and taxicabs An adventure that starts with a morning of bell ringing and ends with a mad dash in a taxi

The phantom parabola Zoe Griffiths investigates paranormal quadratics

Counting caterpillars Peter Rowlett uses combinatorics to generate caterpillars