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A Mathematician’s Guide to Wordle

We invited mathematician and wordplay fan Ali Lloyd to share his thoughts on hit internet word game phenomenon Wordle. If you’re not familiar with the game, we recommend you go and have a play first.

Photo of a mastermind board, showing coloured pegs in rows.
CC BY-SA ZeroOne

When I first saw Wordle I said what I saw many other people subsequently say: “Oh, so it’s a bit like Mastermind but with words? That’s a neat idea”. 

The hunt for almost Pythagorean triples

Pythagorean triples have a long and storied tradition. But what about the near misses?

You’d be surprised how much math[s] you can learn by exploring some of the implications and ramifications of what may seem at first no more than a trivial brainteaser

Martin Gardner

James Grime answers your Shakuntala Devi questions

This is a follow-up to James’s FAQ for the 2014 film The Imitation Game.

Shakuntala Devi is a 2020 Indian Hindi-language film about Shakuntala Devi, a performer of impressive mental calculations, available now on Amazon Prime.

The extraordinary Cardano family

In this guest post by David Benjamin, we explore a little of the life and times of Girolamo Cardano and his interesting family.

Girolamo Cardano (1501- 1576) was at various times in his life a physician, mathematician, inventor, addictive gambler and prisoner. He was the illegitimate son of Fazio Cardano and Chiara Micheria, and the Cardano family was a dysfunctional 16th Century version of the Simpsons.

Doughnuts in the Sand

This is a guest post by semi-regular guest author, mathematician-turned-maths-teacher Andrew Stacey.

I like having something mathematical to think about for times when I’m, for example, waiting in a queue to get into the supermarket. Annie Perkin’s Math Art Challenge has been a good source of such of late. These are a series of mathematically-inspired artistic activities, ranging from designing celtic knots to constructing origami polyhedra and everything in between.

My eye was caught by one on sandpiles – I’ll explain exactly what they are in a moment. One feature that made it attractive was that it was quite simple to write a program to generate diagrams. I find that the maths that interests me usually comes from looking at variations, and for that I need to generate a lot of examples. Doing them by hand quickly becomes laborious. So I whipped up a program (which I later converted to an online version) and ran it a few times to see what happened.


Andrew Stacey: I have a confession to make that would probably get me thrown out of every respectable Mathematics Society – were I to belong to one.

I am not a fan of the Fibonacci sequence.

Neither am I keen on the golden ratio. It’s not even transcendental.

It’s not really their fault, it’s just that they get levered in everywhere whether they belong there or not. Particularly in discussions of nature and beauty, and this is exemplified by that ridiculous origin story. We’ve been subjected to a variety of bizarre origin stories over the years (cough radioactive spider cough) but the rabbit story is another level of bizarre.

So I was intrigued, and then delighted, when one of my students, who is a bee enthusiast, told me about a genuinely natural occurrence of the Fibonacci sequence in the ancestry of bees.

I’ll let her take up the story.