21-card trick – Numberphile

A simple trick with some neat math behind it. More on Numberphile cards at:
More links & stuff in full description below ↓↓↓

More cards video:

This video features Anastasia Chavez:

We did a similar video to this about six years ago with Matt Parker (and 27 cards):

Numberphile is supported by the Mathematical Sciences Research Institute (MSRI):

We are also supported by Science Sandbox, a Simons Foundation initiative dedicated to engaging everyone with the process of science.

And support from Math For America –

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Videos by Brady Haran
Additional editing and animation by Pete McPartlan

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