How many ways can you join regular pentagons? @standupmaths

Uploaded July 2023 | Updated September 2026, 2 weeks ago

Thanks to Jane Street for supporting this video.
janestreet.com/join-jane-street

Curved-Crease Sculptures by Erik Demaine and Martin Demaine
erikdemaine.org/curved

The original paper: "A Complete List of All Convex Polyhedra Made by Gluing Regular Pentagons" arxiv.org/abs/2007.01753

Get your hexagon equivalent here: arxiv.org/abs/2002.02052

Cookie. Clicker. Like that video is going to happen.
arxiv.org/abs/1808.07540

Huge thanks to my Patreon supporters. They keep all my polyhedra convex. patreon.com/standupmaths

CORRECTIONS
- None yet, let me know if you spot anything!

Filming and editing by Alex Genn-Bash
Written and performed by Matt Parker
Produced by Nicole Jacobus
Music by Howard Carter
Design by Simon Wright and Adam Robinson

MATT PARKER: Stand-up Mathematician
Website: standupmaths.com
US book: penguinrandomhouse.com/books/610964/humble-pi-by-matt-parker
UK book: mathsgear.co.uk/collections/books/products/humble-pi-signed-paperback

How many ways can you join regular pentagons?

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$Recursive PowerPoint Presentations [Gone Fractal!] Thanks to Steve Mould for filming with me. Check out his How viruses self assemble video. https://youtu.be/3X6qEE2fHvE We have since made the t-shirt Im wearing available for purchase: https://fotsn.teemill.com/collection/recursive-t-shirt/ We have some free teaching resources for anyone who wants to make a large collaborative fractal! As well as complicated 3D ones weve made a new Think Maths low-prep giant Sierpinski triangle guide. http://think-maths.co.uk/standupmaths-videos?yt-PPT-fractals#PPT-fractals The second channel video takes a closer look at the pptx file and the details of what version of PowerPoint you need to make this work. https://youtu.be/5Mltw6cTb-s Tom Wildenhain has since made far more successful PowerPoint fractals than Steve and I were anywhere near. https://youtu.be/O8l_awjgoMI If you want to see the live An Evening of Unnecessary Detail show: its once a month in London. https://festivalofthespokennerd.com/show/an-evening-of-unnecessary-detail/ Some technical details about the Cantor Set. http://mathworld.wolfram.com/CantorSet.html CORRECTIONS - Nothing yet. Let me know if you spot anything! Thanks to my Patreon supports who do support these videos and make them possible. Here is a random subset: Simon Hutchings Philippe von Bergen Richard Fourie Alan Flett James Tanner Support my channel and I can make more maths videos: https://www.patreon.com/standupmaths Filming and editing by Trunkman Productions: http://trunkman.co.uk Sound production by Peter Doggart Music by Howard Carter Design by Simon Wright MATT PARKER: Stand-up Mathematician Website: http://standupmaths.com/ Maths book: http://wwwh.umble-pi.com Nerdy maths toys: http://mathsgear.co.uk/$

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