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The simplest difficult task
Factorisation is often used in cryptography. But there's something even simpler which turns out to be just as hard.
Should you buy a Valentine’s day present?
For those of you tackling this dilemma, here's your answer...
Binary magic card trick
Behind today's door... A binary magic card trick!
Killing by numbers: the mathematics of warfare
A blast from the past. Modelling battle grounds from ancient Greece.
A counterintuitive result in the theory of traffic flow
Additional roads do not imply faster travel times!
Can we do good more effectively?
Choosing which charity we donate money to shouldn't be an entirely emotional decision.