Calculator Number Trick: rectangle patterns

Here is the original Fermat's Library tweet.
  / 1052544515632959488  

We make Think Maths teaching resources to go with Stand-up Maths videos. For this one we have a cheat sheet to an algebraic proof.
http://think-maths.co.uk/standupmaths...

Many people are asking for the gif. It’s available in different forms in various places online.
https://tenor.com/view/matt-parker-pa...
https://imgur.com/gallery/HyPfz

Originally a homage to the Tim and Eric gif. From this video:    • Calculating π by hand: the Chudnovsky...  

The ticking sound in the video was from here.
https://freesound.org/people/KentVide...

CORRECTIONS
I did not properly think through the hexadecimal example. I meant that any such digits on a base-10 calculator would give multiples of 11. On a true hexadecimal calculator you would get multiples of 17 (or any n+1 for base-n). First spotted by MasterHigure.
Let me know if you spot anything else!

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Music by Howard Carter
Filming and editing by Matt Parker
Design by Simon Wright

MATT PARKER: Stand-up Mathematician
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