Theory of numbers: Multiplicative functions
Channel: Richard E Borcherds
Date: 2021-01-26

This lecture is part of an online undergraduate course on the theory of numbers.

Multiplicative functions are functions such that f(mn)=f(m)f(n) whenever m and n are coprime.  We discuss some examples, such as the number of divisors, the sum of the divisors, and Euler's totient function. 




For the other lectures in the course see https://www.youtube.com/playlist?list=PL8yHsr3EFj52Qf7lc3HHvHRdIysxEcj1H