# You're reading: Travels in a Mathematical World

### Population modelling in the Marvel Cinematic Universe

This post contains spoilers for the end of Avengers: Infinity War.

One day, a couple of months ago, I was walking my son to nursery and he asked what I was doing that day. I said I was going to do some teaching. What about? he asked. Well.

### Ning Nang Nong Latin square

My son is obsessed with the Spike Milligan nonsense poem ‘On the Ning Nang Nong’. Here’s a video of Spike reciting it.

This weekend, he asked me to help him learn it. I’ve tried to memorise it before, to save having to find the book when he wants me to recite it. But somehow, it’s never quite stuck. I can remember all the bits and the basic order (Cows-Trees-Mice), and know what happens after the lines ending “Nong” (“Cows go bong”), “Ning” (“Trees go ping”) and “Nang” (“Mice go clang”). What I struggle with is remembering which order the “Ning”, “Nang” and “Nong” go before the one that rhymes with what comes next.

At the weekend, I wrote “Ning”, “Nang” and “Nong” on pieces of paper and we rearranged them as we read the poem. I realised my difficulty is a mathematician pattern-spotting one. There’s a not-quite Latin square embedded in the poem.

### Pringle stack mathematics

Pringles ran a Super Bowl advert. In case you’re looking for ways to give Pringles more money, apparently you can buy several tubes of Pringles and mix the flavours. (Pringles are a type of food. Super Bowl is a kind of sport. None of that matters, what matters is…) The advert shows a man stacking three Pringles together and claims there are 318,000 possibilities.

### LaTeX/TikZ to draw a star graph $K_{1,n}$
For a diagram for a class this week, I’ve written a LaTeX command to draw star graphs using TikZ. A star graph $K_{1,n}$ is a graph with a single central node, $n$ radial nodes, and $n$ edges connecting the central node to each radial node. I am sharing this here in case it is useful to anyone else.