I was bored in a hotel room, so I went and bought 72 pencils. You can buy the same pencils on Amazon here: https://www.amazon.com/Staples-Yellow-Pencils-Dozen/dp/B00BQ3ALD6?_encoding=UTF8&tag=stanupmath-20 Download the Stand-up Maths theme! https://standupmaths.bandcamp.com/ George Hart's 72 Pencils: http://www.georgehart.com/sculpture/pencils.html Alejandro Erickson's hexastix instructions: http://alejandroerickson.com/j/2011/09/27/090-how-to-make-hexastix-detailed-photo-instructions.html My show at MoMath in New York on Sunday 23 October: https://in.momath.org/civicrm/event/info?reset=1&id=744 This video is in no way sponsored by Staples. If anything, they're probably slightly annoyed at me for messing around in their fancy office chairs. CORRECTIONS: None yet. Let me know if you spot anything. Support my videos on Patreon! https://www.patreon.com/standupmaths Music by Howard Carter Design by Simon Wright MATT PARKER: Stand-up Mathematician Website: http://standupmaths.com/ Maths book: http://makeanddo4D.com/ Nerdy maths toys: http://mathsgear.co.uk/