# SATURDAY

## SESSION 1a : 14:10

### Phil Harvey : Initialistic Determinism

How you can improve your chance of success in life.

### Alison Kiddle : Pastamathics

Spaghetti on toast is everybody's favourite quick and easy tea, but have you ever stopped to analyse the maths on your plate?

### Mick de Pomerai : Mass of a Black Hole

Short history of ideas on orbits & gravity to introduce maths needed to calculate the mass of Sagittarius A* from Keck telescope data (animation) - available on internet. Essentially potted math history with added arithmetic (data to take away)!

### Hugh Hunt : Chain on a Cone

A thin light chain with a heavy pendant is displayed in a jeweller's shop hanging on a smooth conical stand. What is the cone angle above which the chain will slip off the stand under the weight of the pendant down the slope?

### Claire Cohen : How Lucky is the Bonus Ball

A brief look at the numbers people chose during a "bonus ball" competition, patterns in the numbers chosen and possible reasons for this.

### Laurence O'Toole : Guessing With Lies - A Magic Trick

A twist on an old Christmas cracker trick. With lying. For science!

### Adam Townsend : The coin distribution problem revisited

Why do self-checkout machines give the worst change? Are they better in other countries? Using real price data from the ONS, we ask: would getting rid of the penny fix this problem, or is there a better, more ridiculous solution? (Yes)

### Martin Harris : Pleasing Pictorial Proofs and Ptolemy's Ptheorem

A short discussion on the usefulness of pictorial proofs, and a new one for Ptolemy's Theorem of Cyclic Quadrilaterals.

## SESSION 1b : 15:25

### Samuel Hansen : The long tail of mathematical citations

In this talk I will explore how age and citation counts are related in highly cited mathematical papers with a specific focus on mathematical researches unique aging characteristics.

### Gavan Fantom : Doing trigonometry in your head while trying to land a plane

There's a lot of maths involved in flying a plane. Fortunately most of it can be done on the ground, but there are some calculations that pilots do while in the air. Imagine you're on final approach, less than a minute from the runway. Can you use trigonometry to decide if it's safe to land?

### Rob Low : A minus times a minus is a pain

We all learn quite young that a minus times a minus is a plus, and the reason given by the teacher is all too often some variation on "Because I (the book) say(s) so". Why should we believe it?

### Eleanor Doman : A needling problem from embroidery

Blackwork is a type of embroidery that traditionally that is supposed to look the same on the front and back of the material and is usually based off geometric patterns. But what kind of patterns can we use, and can we prove mathematically that they will look the same on both sides.

### Kevin Houston : Where was that taken?

Can we use mathematics to determine where the photographer stood to take a photograph?

### Mike Frost : Piet Hein - Pirate

My day job in control engineering takes me to steel mills around the world. When I visited a mill in the Netherlands I was intrigued to find that the hotel conference suite was named for Piet Hein. Why did a dutch hotel have a room named for a danish mathematician much revered by recreational mathematicians? The answer was not what I expected.

### Peter Rowlett : Counting caterpillars

We bought a new toy for our three-year-old, a robot caterpillar. On its packaging, this promised its pieces could be arranged into “endless combinations”. Of course, I had to investigate a more sensible number! And it proved to be not a completely straightforward combinatorics problem.

### Tung Ken Lam : Action Modular Origami

This talk explains what action modular origami is and how it intrigues and delights. What are its origins and current developments? Briefly, action modular origami involves folding and joining paper together (without cutting or gluing) into sculptures that move or change shape. They can be put in six categories (ignoring things that you throw): sliders; flexagons; rotating rings; magic wallet models; spinners and wheels; 3D shapeshifters. Are they papercraft, practical geometry, kinetic sculpture, a source of mathematical learning or fun moving toys?

## SESSION 1c 16:30

### Ben Sparks : Cat and Mouse ...

A puzzle for you ... will include GeoGebra (of course)...

### Rachel Wright : An Unexpected Parallel

Pierre de Fermat was not the only person to make an off-hand comment that gave subsequent generations a thundering headache...

### Derek Couzens : Using maths to solve a socially embarrassing situation

How mathematics helped me overcome a very embarrassing problem at the wedding of Prince Harry and Meghan Markle.

### Alex Burlton : 180 ways not to model a darts player

What happens when you are mediocre at darts and have too much time on your hands? I discuss my attempts to generate an equally crummy opponent - with some surprising results.

### Christian Lawson-Perfect : Zeckendorf cup arithmetic

Having a baby hasn't been a complete distraction from maths.

### Steve Plummer : 42

Not quite life, the universe and everything.

### Barney Maunder-Taylor : Collapsible polyhedra

A demonstration of various homemade polyhedra (all the Platonic solids and some of the Archimedeans) that fold flat.

## SESSION 1d : 17:40

### Louise Mabbs : Jacob's Ladders - fabric and paper experiments

In 2006 I developed a fabric version of the traditional Jacob's Ladder 2-strip fold for my fabric origami book. I realised there were lots of benefits of making it in fabric rather than paper, due to the stretch and distortion opportunities, but I wasn't entirely happy with the finished result. I returned to it this year for a poster presentation at 7OSME, finding a better solution to my fabric problem and also experimented with folding up to 8 strips together in different formats. The resulting techniques cover origami, braiding, weaving and several other skills and some fascinating structures.

### Tom Reddington : Banach-Tarski: just make peace with it

I've had many arguments and several pub fights due to people's reluctance to accept the Banach-Tarski paradox. Here are the facts. Embrace them.

### Alison Eves : Magic magic squares

A quick introduction to magic squares, some interesting facts, and some links to magic squares in art and history.

### Sydney Weaver : The Sound of Silence

An exercise in the 4 memory types demonstrated by the Rubik's Cube and a parody of a well known song

### Alaric Stephen : Generating Hard Puzzles Using Graph Theory

I will highlight a method for making word based puzzles to an arbitrary amount of difficulty using a quirk of Hamiltonian graphs.

### Colin Wright : e's in a twist

Square roots, simple algebra, a step in an odd direction, and maybe we can find interesting connections.

### Elevator Pitches : For Saturday night tables

We'll allow anyone running a table of activities on the Saturday evening a chance to explain what their activity will be, so you can choose how to spend the evening.

# SUNDAY

## SESSION 2a : 09:00

### Katie Steckles : The Unwanted Solid

You may have heard of Archimedean solids - a category of thirteen 3D shapes with particular properties. But did you know that there's actually a fourteenth Archimedean solid? I will argue the case for allowing the Pseudorhombicuboctahedron to join the club.

### Martin Chlond : The Travelling Salesman Problem: A couple of whimsical applications

A couple of quirky uses of TSP algorithms

### Jonathan Welton : Platonic Moboids

Using paper, scissors and glue, platonic moboids knot together two familiar mathematical concepts, and produce a third.

### Callum Mulligan : Ray casting and Rabbits

Ray Casting is used in a multitude of ways to solve intersection tests. One of my students did something brilliant and used it in an alternative way. This got me thinking, So in this talk we will look at some fun uses for Ray Casting [Including how it can be used to spawn Rabbits in a videogames!] and the mathematics behind it.

Something about shells. My 2nd favourite part of Robert McNeill Alexander's book, Animals, is about the formation of shells. Biomechanics stuff. So I thought I'd share some of it.

### Tarim : Snake Bridges

How canal engineers used topology before the term was even coined

## SESSION 2b : 10:05

### Adam Atkinson : Conspiracy of Silence

Many textbooks and courses say nothing about a certain topic. Sometimes there are almost amusingly dark hints along the lines of "There is another possibility. But we shall speak no further of it." This description is hinting darkly but the talk itself will break the conspiracy wide open.

### Will Kirkby : Digital Art and Distance Functions

A brief exploration of signed distance functions and their use in real-time computer graphics.

### Jo Morgan : Changing Contexts

A quick look at how the contexts used in school mathematics questions have changed over the years

### Pedro Freitas : Ubiquitous Permutations

Last year I presented a card trick which relied on a certain way of mixing cards. On the train to the MathsJam gathering, I learned more about the permutations that made the trick work.

### Alistair Bird : The four-and-a-half colour theorem

Spoiler: The truth of the famous 4-colour theorem immediately implies that the 4˝-colour theorem is also true. But how can you have half a colour? And why bother investigating a theorem when we already know the answer?

### Michael Gibson : A New Trick for Old Dogs

The "well known" Five-Card-Trick involves a volunteer choosing 5 cards and giving them to Magician A who looks at them and arranges them with 4 cards showing and one hidden. Based on this Magician B can then say what the hidden card is. I will describe and perform a new version of this trick in which only 1 card is showing and Magician B has to say what all 4 of the hidden cards are.

## SESSION 2c : 11:00

### Matthew Scroggs : Mathsteroids

I will talk different ways to represent a sphere as a flat surface using Mathsteroids (http://www.mscroggs.co.uk/mathsteroids/), an asteroids-style game in which you can play on a sphere with different representations.

### Stefania Delprete : MathsJam in Python

How our group solved one or two MathsJam challenges using Python, after trying and trying. We wanted to resist using our laptops but... "resistance is futile".

### Stuart Eves : Do the planets fit between the Earth and the Moon?

Is there room between the Earth and the Moon to fit all the planets in the solar system? Possible answers are "yes", "no", or "sometimes". Find out which answer is correct...

### Francisco Albuquerque Picado : A Comic, a Painting, Triangles, and Squares

A comic leads to a painting, which allows us to discover a connection between triangular numbers and sums of squares.

### Pat Ashforth : Extending Tables

Looking at patterns in tables

### Tiago Hirth : From Pebbles do Nimbers and Stars

Quick run through 500 years of history related to the game of Nim and invitation to participate in Recreational Mathsmatics projects.

## SESSION 2d : 11:50

### Colin Beveridge : A proof without words

1^2 + 2^2 + 3^2 + ... + n^2 = n(n+1)(2n+1)/6. But who can remember that?

### Robie Basak : Measuring sticks

Using measuring sticks to perform arithmetic

### Andrew Macdonald : So, about Ghandi

Addition, subtraction and negative numbers in binary computing

### Sam Hartburn : Battle of the slinkies: paper vs plastic

Can an origami slinky outperform a cheap plastic one? Probably not, but I'll give it a try anyway.

### Announcements : Competition results

The results of the MathsJam Bakeoff, and the Competition Competition, and each of the individual competitions within the Competition Competition, will be announced.