Every vertex has an even degree, yet the picture cannot be drawn with a single stroke.
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Prize crossnumber, Issue 20
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Chalkdust issue 09 – coming 15 March
Read the magazine, and come to the launch party!
Christmas conundrum #4
Can you solve four puzzles to reveal the hidden message?
Crossnumber winners, issue 04
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Page 3 model: When zombies attack
Every issue we feature another great model on page 3 of our magazine. This time we look at what to do when zombies attack.
A Fields Medal at UCL: Klaus Roth
Klaus Roth and his work