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Say happy birthday to Christopher Zeeman on his 90th

Maths hero Christopher Zeeman will turn 90 in February. Normally when a mathematician reaches a big round number of years, there’ll be a celebratory day of lectures or even a small book. The LMS has decided to take things even further by setting up a website to collect people’s birthday wishes, as well as personal stories and photos, for the Z-man (as he’s known in downtown Warwick). They’ll all be collected into a book and presented to him at the launch of the LMS’s new online archive.

So if you want to say happy birthday to Sir Christopher, go to the Zeeman Turns 90 website.

via The London Maths Society on Twitter.

Just Get 10


Here’s a new numberiffic game from Veewo, the people who made noted Threes-a-like 1024 (which begat 2048, which inevitably begat 2048: Harry Styles edition).

In Just Get 10, you have to get at least nineteen combine numbered blocks until you get one with a 10 on it. If you tap two adjacent blocks with the same number, they’re replaced by a single block with the next number up.

It’s alright.

Announcing The Aperiodical’s Best Maths Pun of 2014 Competition


Here’s one of my favourite maths puns.

What’s yellow and equivalent to the axiom of choice?

Zorn’s Lemon!!!!!!!!

I like it because it’s a real groaner, but to even begin to see what it’s punning on you have to know some pretty obscure facts about set theory. That makes it an ideal maths pun.

Maths puns abound (both upper and lower). Most of the time they make your eyes roll so badly that gimbal lock becomes a consideration, but a real corker makes all the years of mathematical study worthwhile.

Since the year is about to end, we thought it’d be a fun idea to collect some new maths puns, and run a quick competition to find 2014’s best offering (or the local maxipun at 2014, as we like to call it).

Watch out! I’m a blue whale and I’m about to land on you!


I don’t know why this question popped into my head, but it’s been sitting there for the past week and showing no signs of moving on.

Suppose an enemy of mine threw a friendly blue whale at me. Being a friendly whale, it makes the blue-whale-noise equivalent of “DUCK!” to warn me it’s coming.

How quickly does the whale need to be travelling for its warning to be useful?

Apparently I’m not a maths genius (or, On the Subject of Parcel Sizes)

This article on BBC News caught my eye because it has “maths” in the headline. Yes, I’m that easily pleased.

Somewhere in the middle, it says that myHermes requires the “volumetric area” of a parcel to be less than 225cm. That’s right: the “volumetric area” is neither a volume nor an area but a length. Anyway, the formula for volumetric area of a package with sides $a,b,c$, where $a \leq b \leq c$, is

\[ 2(a+b) + c \]

(Importantly, $a$ and $b$ are always the two shortest sides of the package)

So the constraint is

\[ 2(a+b) + c \leq 225 \]

In the next paragraph is the puzzling statement that the maximum allowable volume for a package is $82.68$ litres, or $82680$ cm3. How did they get that?

I decided to do some calculus of variations, or whatever it’s called.