More from Chalkdust
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!
Advent puzzles I
Behind the second door of the advent calendar, there is a puzzle
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!