On 30–31 October 2020, a group of maths presenters got together some mathematicians, magicians and other cool people to put on a 24-hour long online YouTube mathematical magic show. Each half-hour had a different special guest sharing a mathematical magic trick of some kind, giving a total of 48 tricks for you to watch and puzzle over (and since was Hallowe’en, we included some treats as well).
The guests included:
- Mathematician and RI Christmas Lecturer Hannah Fry
- Stand-up Mathematician Matt Parker
- Professional speed Rubik’s cuber Sydney Weaver
- Popular science author Simon Singh
- Mathematician and presenter Katie Steckles
- Numberphile and YouTube star James Grime
- Mathematician and author Eugenia Cheng
- University Challenge star Bobby Seagull
- YouTuber/Game Show host Tom Scott
- Maths teacher and BBC Radio 4 puzzle writer Susan-Louise Okereke
You can find a full list of guests, and links to their parts of the show here.
The show took place alongside Mark Watson’s 24-hour comedy show Watsonathon, which we appeared on at three points during the day/night (first, second, third). Both shows were raising money for the charity Turn2Us which helps people in low-income jobs & gives out emergency grants, and the Comedy Support Act, supporting comedians and other performers who have little/no income at this time. You can still donate on Mark’s fundraiser page.
At 21:00-21:30 GMT, Zoe Griffiths (, ) joined us and successfully memorised the results of 40 coin flips. Zoe is involved in upcoming events with think-maths.co.uk, mathsinspiration.com, and cosmicshambles.com/ninelessons.
At 21:30-22:00 GMT, Phil Bell-Young (, ) joined us to perform a card trick that everyone could also try at home.
At 22:00-22:30 GMT, Matt Parker (, , ) joined us to (eventually) perform a very unlikely card trick.
At 22:30-23:00 GMT, Susan Okereke (, , ) multiplied some two digit numbers by 11 very quickly, and showed us how to multiply quickly by 6, 7, 8 and 9 using her hands.
At 0:00-0:30 GMT, Raj Shah (, ) impressed Ben with some magic grids of numbers.
At 0:30-1:00 GMT, Tom Crawford (, , ) worked out how to do Ben’s dice and then performed it himself for the very first time.
At 1:00-1:30 GMT, Matthew Scroggs (, ) taught some matchboxes to beat Ben at Nim. He also treated us by releasing a new issue of Chalkdust, a magazine for the mathematically curious
At 1:30-2:00 GMT, Gord! (, ) impressed us with some square arrangements of cards.
At 2:00-2:30 GMT, Ron Lancaster showed us a trick involving cards and dice.
At 2:30-3:00 GMT, Scott Kim (, ) amazed us with some ambigrams.
At 3:30-4:00 GMT, Jack Harrison considered 1 + 2 + 3 + 4 + 5…
At 4:00-4:30 GMT, Paddy Moore () showed us some simple but impressive card tricks.
At 4:30-5:00 GMT, Dan Finkel (, ) used numbers chosen by the YouTube chat to perform a trick.
At 5:00-5:30 GMT, Ayliean MacDonald (, , ) tore a loop of fabric in half to make two interlinked loops of fabric.
At 5:30-6:00 GMT, James Arthur (, ) showed us a trick involving addition of unit fractions.
At 6:00-6:30 GMT, Jimi Jibodu showed us card tricks by Bob Hummer.
At 6:30-7:00 GMT, Tom Briggs (, ) worked out fifth roots at incredible speed.
At 7:00-7:30 GMT, Tom Scott (, ) brought along paper and scissors to do some folding and cutting for a trick with Katie Steckles.
At 7:30-8:00 GMT, Sydney Weaver (, ) performed some amazing feats with Rubik’s cubes.
At 8:00-8:30 GMT, Tony Mann (, ) showed us a card trick from his primary school days.
At 8:30-9:00 GMT, Kyle D Evans (, ) showed us a trick on a clock.
At 9:00-9:30 GMT, Alison Eves () worked out Bobby’s birthday. Alison coordinates maths masterclasses for the Royal Institution (, ).
At 9:30-10:00 GMT, Chris Smith (, ) hid the number 123 in a skull, confused Bobby with a clock, and did a song. Chris sends out a weekly maths newsletter full of puzzles, lesson ideas, resources, and trivia. Email firstname.lastname@example.org and Chris will be happy to sign you up for the newsletter!
At 10:30 GMT, Sophie Maclean (, , ) took over from Bobby to introduce our next guests. You can listen to Sophie’s podcast on Spotify.
At 10:30-11:00 GMT, Jo Morgan () was the volunteer for a trick performed by Sophie, then Sophie and Jo worked out how the trick worked.
At 11:00-11:30 GMT, Kevin Houston (, , ) performed some card tricks using his unbelievable ability to perform a perfect shuffle.
At 11:30-12:00 GMT, Tiago Hirth performed lots of tricks. Many of the involved a chain and a ring.
At 12:00-12:30 GMT, Bobby Seagull (, , ) made Fran think about an orange kangaroo.
At 12:30-13:00 GMT, Laurence O’Toole worked out Fran’s number after 8 questions even though she lied.
At 13:00-13:30 GMT, Goran Newsum () got Katie’s disembodied hands to perform a dice trick.
At 14:00-14:30 GMT, Colin Wright (, ) dealt a deck into 13 piles of 4 then made four straights from the piles. But is it always possible, or was he just lucky?
At 15:00-15:30 GMT, Vicky Neale (, ) folded some paper and found a parabola, then drew some straight lines to find some other surprise curves. Vicky’s new book, Why Study Mathematics? came out this week. There are templates for some interesting curve stitching on her website.
At 15:30-16:00 GMT, Simon Allen made James divide some numbers between 7, 11 and 13.
At 16:00-16:30 GMT, James Grime (, ) got the other James to multiply some one digit numbers together, the guessed a missing digit. On 20 November, James is running virtual maths retreats with Katie Steckles for year 7-9 and year 10-11 students.
At 16:30-17:00 GMT, Ben Sparks (, ) showed Jon a card trick, then taught Jon how to do it.
At 17:00-17:30 GMT, Katie Steckles (, , ) showed Jon a trick involving four digit numbers made by three rods. On 20 November, Katie is running virtual maths retreats with James Grime for year 7-9 and year 10-11 students.
At 17:30-18:00 GMT, Andrew Jeffrey () showed us a metal squircle, and gave Jon a fantastic prize…
At 18:00-18:30 GMT, Hana Ayoob (, , ) showed us how to turn a playing card inside out.
At 18:30-19:00 GMT, Ash Frankland (, ) showed us some superflips on his Rubik’s cube.
At 19:30-20:00 GMT, Simon Singh (, ) showed us a physics trick. Simon runs Parallel Maths (), a website full of maths resources for mathematicians aged 10 to 16.
At 20:00-20:30 GMT, Eugenia Cheng (, ) showed us how to find a hexagon in a cube, and cut a Battenburg. Eugenia’s newest book X+Y: A Mathematician’s Manifesto for Rethinking Gender and her first children’s book Molly and the Mathematical Mystery are both out now!
At 20:30-21:00 GMT, Hannah Fry (, ) joined us for a chat.
At 21:01 GMT, we went to sleep.
At around 20:45 GMT on Friday 13 November, we showed off some highlights of the 24 Hour Maths Magic Show on Mark Watson’s Watsonathon Encore.