158,962,555,217,826,360,000 (Enigma Machine)

Alex Bellos discusses how the Incans used knots in string (Quipu) to record numbers.Check out Brilliant (get 20% off their premium service): https://brillian...

The Nazi's Enigma Machine - and the mathematics behind it - was a crucial part of World War II.

Flaw video at: http://www.youtube.com/watch?v=V4V2bpZlqx8

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Dr James Grime demonstrates the machine and discusses its many configurations.

James' "day job" is touring with the Enigma machine - he could even visit you - see more at http://enigma.maths.org/content/project-officer