63 and -7/4 are special

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...

Dynamical sequences, prime divisors and special exceptions.

Featuring Dr Holly Krieger from MIT.

More primes: http://bit.ly/primevids
More videos with Holly Krieger: http://bit.ly/HollyKrieger

Since this was filmed, Holly has become a mathematics Lecturer at the University of Cambridge and the Corfield Fellow at Murray Edwards College.