We must start and end at one of the bottom points
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Top ten vote issue 09
Vote for your favourite Chalkdust issue
On the cover: Chladni figures of a square drum
Find out more about the patterns on the cover of Issue 07
Advent quiz
Behind today's door... A quiz!Top Ten vote: Colours of chalk
Vote for your favourite colour of chalk for Issue 04: is it white, yellow, or the Post Office Tower?
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Are you a winner?
Optimal Pac-Man
Matthew Scroggs spends too much time beating this arcade classic.