Just emailed 125 people. Eeeeep!

I've started getting youtube adverts which seem to be aimed at people with a tepid sludge where their critical faculties should be. Like the video equivalent of phishing emails with scattered typos to filter out people who think twice about things.
Should I be worried that I've been identified as a potential mark?

Printed a small folding dodecahedron from TPU to see how it would turn out, then wasn't sure what to do with it, so...

Nailed it! This video shows the latest version folding easily in real time. You can hear my Prusa Mini+ in the background printing the next one! The print files are at Printables.com here: printables.com/model/217716-sn

I solved 15 in 2!
✓↔↔✗✗
✓✓✓✓✓
somethingorotherwhatever.com/o

'splittance' is a fabulous word

The last wrinkle for standard arithmetic is that exponentiation is right-associative: while for the other operations you work left-to-right:
1 − 2 − 3 = (1 − 2) − 3,
the order goes the other way for exponentiation:
1 ^ 2 ^ 3 = 1 ^ (2 ^ 3)

Here are some animations to illustrate. In the first, the operations happen left-to-right, so they appear in the same order in the output as in the input.
In the second, the addition must happen after the multiplication, so it's held back.
In the third, brackets ensure that the addition happens first.

The shunting yard algorithm neatly solves the problem of translating a mathematical expression written in infix notation (operators go between the numbers/letters) to postfix notation (operators go after the things they act on).

The core problem is that you need to work out what just what an operator applies to: with the order of operations, it might be just one number, or it might a large sub-expression.

The algorithm solves this by holding operators on a separate stack until they're needed

A while ago @davidphys1 asked why nobody had made animations of the shunting yard algorithm with cutesy trains.
There is no surer way to summon me!
I've spent some of my spare time over the bank holidays making exactly that: somethingorotherwhatever.com/s

Woohoo, I just made £1 when someone bought this t-shirt of a recycled Dudeney graphic that took me very little effort: redbubble.com/people/christian

Found in the box of eggs I just bought. Apparently the chicken is calculating a Lorentz contraction.

Playing with the pack of cards on my desk, something just happened that I didn't expect!
Look at the deck with the cards face-up. Here's a rule: look at the top card. Draw that many cards from the deck. Repeat until the deck is empty.
I did this, and dealt out exactly the right number of cards (at the end, I had 3 cards left and the top card was a 3).

What's the probability of this happening?

I was invited onto BBC Radio Kent today (I seem to have been added to some sort of list!) to talk about Imperial units. Listen at bbc.co.uk/sounds/play/p0c6bvxk from 1:42:10.

I wrote about my Prime Run game on @aperiodical: aperiodical.com/2022/05/prime-

Ooof. Sometimes it's easy, sometimes it's very hard.

I solved 9 in 8!
somethingorotherwhatever.com/o

I've spent an entire day making this illustration for an @aperiodical post. I'm glad I stuck with it, because for ages it was absolute bums and then suddenly it all came together!

Lately the baby has learnt to say his name in response to "who's a lovely boy?", and he gets big smiles.

Just now I said "who's a lovely boy?" and he said "dad!" and I just 🥰

Where do I start... Ah, yes, an interesting question: what would the 3D Koch curve (or surface, whatever) be like?