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.

# You're reading: Travels in a Mathematical World

### 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.

### Finding an equation that has the same solution when rotated

I made this. Here’s how…

### Christmas images using parabolic curves and TikZ

Katie is running an Aperiodical advent calendar (Aperiodvent 2018), with fun maths Christmas treats every day. Behind the door for 7th December was Parabolic Sewing.

This is not unrelated to what I submitted as my entry to The Big Internet Math-Off last summer. I have been revisiting this idea ready for a class next week in my second year programming module.

### 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.

### Baking Babylonian cuneiform tablets in gingerbread

The MathsJam conference has a baking competition. My friend the archaeologist Stephen O’Brien tweeted a while ago a link to a fun blog post ‘Edible Archaeology: Gingerbread Cuneiform Tablets‘. Babylonian tablets are among the earliest written evidence of mathematics that we have, and were produced by pressing a stylus into wet clay.

So it was that I realised I could enter some Babylonian-style tablets made from gingerbread.

I made a gingerbread reconstruction of a particular tablet, YBC 7289, which Bill Casselman calls “one of the very oldest mathematical diagrams extant“. Bill writes about the notation on the tablet and explains how it shows an approximation for the square root of two. I’m sure I didn’t copy the notation well, because I am just copying marks rather than understanding what I’m writing. I also tried to copy the lines and damage to the tablet. Anyway, here is my effort:

In addition, I used the rest of the dough to make some cuneiform biscuits. I tried to copy characters from Plimpton 322, a Babylonian tablet thought to contain a list of Pythagorean triples. Again, Bill Casselman has some interesting information on Plimpton 322.

Below, I try to give a description of my method.