Uploaded May 2024 | Updated September 2026, 2 weeks ago

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Find out more about Jane Street’s programmes running across the world:
bit.ly/sum-janestreet-programs

Including the WiSE course which is open to self-identifying women and gender-expansive university students and incoming students: janestreet.com/join-jane-street/programs-and-events/wise

Check out KangarooPhysics’ original gif showing the cross-section through the packing arrangment: https://x.com/kangaroophysics/status/1491858072251342850?s=46&t=EVDbN01K_p7T27Gd23R0bw
And Daniel Piker’s amazing 3D model: sketchfab.com/3d-models/rod-packing-7directions-2-e56a6e899b2b4ef4bb458c66343363e4
More detail on rod packing in this paper: journals.iucr.org/paper?S010876730001151X

If you want to watch the extended cut, with every excruciating, pencil-pushing moment included, head over to this video on the second channel: youtube.com/watch?v=EsBqeGtThW8

You can also watch the original "How to build a Hexastix in 72 easy steps" if you just want to build a Hexastix. In 72 easy steps. youtube.com/watch?v=DelH1S32dOg

If you need 85 custom pencils in your life (The 67 you need, plus we've put in a few spares) you can buy a set over on Maths Gear. Elastic bands are not included.
mathsgear.co.uk/products/prism-pencils-pack-of-85

Huge thanks to my Patreon supporters. They are as special as a triangular pencil. 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
Love Triangle: mathsgear.co.uk/products/love-triangle-by-matt-
parker-signed
All UK options: penguin.co.uk/books/443151/love-triangle-by-parker-matt/9780241505694
All USA options: bit.ly/3wCTesR