Click here to win prizes by solving the puzzle Advent calendar.
Click here to win prizes by solving the puzzle Advent calendar.


Welcome to

It's nearly Christmas and something terrible has happened: you've just landed in a town in the Arctic circle with a massive bag of letters for Santa, but you've lost to instructions for how to get to Santa's house near the north pole. You need to work out where he lives and deliver the letters to him before Christmas is ruined for everyone.
Due to magnetic compasses being hard to use near the north pole, you brought with you a special Advent compass. This compass has nine numbered directions. Santa has given the residents of the town clues about a sequence of directions that will lead to his house; but in order to keep his location secret from present thieves, he gave each resident two clues: one clue is true, and one clue is false.
The residents' clues will reveal to you a seqeunce of compass directions to follow. You can try out your sequences on this map.
Behind each day (except Christmas Day), there is a puzzle with a three-digit answer. Each of these answers forms part of a resident's clue. You must use these clues to work out how to find Santa's house.
Ten randomly selected people who solve all the puzzles and submit their answers to the logic puzzle using the form behind the door on the 25th will win prizes!
The winners will be randomly chosen from all those who submit their answers before the end of 2020. Each day's puzzle (and the entry form on Christmas Day) will be available from 5:00am GMT. But as the winners will be selected randomly, there's no need to get up at 5am on Christmas Day to enter!
You can find more infomation about this competition, in this blog post.
On this website, you can find my blog and a collection of puzzles. You can also find details of my academic work and information about pop maths and outreach talks that I give. You can use this handy tool to help you decide what to do first.
Recent blogs (click to read).
My most recent blog post is Christmas (2020) is coming!. Other highlights of the blog include:
If you're not sure where to start, you could try reading a random article or taking a suggestion from this handy tool.

Recent puzzles (click to read).
New puzzles are posted on many Sundays, with answers posted on Monday. The most recent collection is Advent calendar 2019.
Some of my favourite puzzles are:
Every December, I post an Advent calendar full of puzzles. You can view the puzzles from the 2019 calendar here.
Again, a random puzzle or a suggestion from this handy tool could be good places to start.

 Who am I? 
My face.
I am Matthew Scroggs. I like maths.
I currently a postdoctoral research associate in the Department of Engineering at the University of Cambridge. Before this, I did a PhD in the Department of Mathematics at UCL and before that I obtained a Master's degree in mathematics at the University of Oxford. Between Oxford and UCL, I worked as a maths teacher in a secondary school. During my PhD, I began working on the open source boundary element method library Bempp. During my postdoc at Cambridge, I began working on the open source finite element library FEniCS. You can find more about my work on the academic page.
You can regularly find me at London MathsJam (second last Tuesday of the month), the MathsJam Gathering (yearly) and EMF Camp (every two years). I write the crossnumber (as Humbug), puzzles and articles for Chalkdust Magazine. For more non-work related articles and talks, see the talks page.
If you would like to reuse any of my content, please get in touch.

Some numbers

 I have written 88 blog posts.
 I have posted 289 puzzles.
 I have published 5 papers (and submitted 2 more).
 I have tweeted 5613 tweets.
 I have tooted 93 toots.
 I have 59 public repositories on GitHub.
 I have contributed 14 sequences to the OEIS.
 I have written 2 LaTeΧ packages.
 I have 171 reputation on Math Stack Exchange.
 I have solved 122 problems on Project Euler.
 I have run 33 parkruns.
 I have run 11 half marathons, and 1 marathon.
 I have found 74 geocaches.
 My Erdős number is 5.
 My Bacon number is ∞.
 My Sabbath number is ∞.
 My Erdős–Bacon number is ∞.
 My Erdős–Bacon–Sabbath number is ∞.
© Matthew Scroggs 2012–2020