Introduction to number theory lecture 52. Nonvanishing of L series at s=1.

This lecture is part of my Berkeley math 115 course "Introduction to number theory" For the other lectures in the course see    • Introduction to number theory (Berkeley Ma...   We sketch how to show that Dirichlet L functions do not vanish at s=1, completing the proof of Dirichlet's theorem. The textbook is "An introduction to the theory of numbers" by Niven, Zuckerman, and Montgomery (5th edition).