Introduction to number theory lecture 1.

This lecture is the first lecture of my Berkeley math 115 course "Introduction to number theory" For the other lectures in the course see https://www.youtube.com/playlist?list=PL8yHsr3EFj53L8sMbzIhhXSAOpuZ1Fov8 This lecture gives a survey of some of the topics covered later in the course, mainly about primes and Diophantine equations. The textbook is "An introduction to the theory of numbers" by Niven, Zuckerman, and Montgomery (5th edition).