Plus.Maths.org
List by Author: Marianne Freiberger
The 36 officers problem 
Euler may not have cracked this problem completely, but it led to a lot of important work, including on what we today know as sudoku.
The knight's tour 
Can you move a knight on a chessboard so that it visits every square exactly once? Euler was one of the first to analyse this problem systematically, but some questions about it are still open today.
The bridges of Königsberg 
Can you find a path through on this city map that crosses every bridge exactly once? Euler's answer to this problem started off the filed of graph theory.
Primes without 7s 
James Maynard, one of the prize winners at the European Congress of Mathematics 2016, is counting primes that don't have 7s in them. But why?
Blood, oil and water 
Sara Zahedi has won a prestigious prize at the European Congress of Maths. Your future medical diagnoses, and even the welfare of sea life, may depend on her work.
Citizen scientists count sunflower spirals 
Does the famous Fibonacci sequence always appear in sunflower seed heads?
A ridiculously short introduction to some very basic quantum mechanics 
Some general ideas in very few words and without equations.
Why quantum mechanics? 
Why did physicists at the beginning of the 20th century feel they needed a new — and strange — theory?
Snakes and adders 
How can an electronic device fed on a diet of 0s and 1s perform complex tasks? We explore the workings of computers using an example.
Andrew Wiles wins Abel Prize! 
One of the greatest honours in maths has been awarded for the proof of Fermat's last theorem.