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The undisputed top ten puzzles this season
The Secret Lives of Numbers
We review the fourth of this year's nominees for Book of the Year
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Sam Hartburn attempts the impossible
What’s hot and what’s not, issue 07
Fashion is fleeting, Chalkdust regulars are not.
Chalkdust’s Christmas conundrums
As the festive season strikes again, we'll be dishing out more fiendish puzzles – this time with prizes!
The simplest difficult task
Factorisation is often used in cryptography. But there's something even simpler which turns out to be just as hard.