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Introduction to number theory lecture 32. Calculation of the Legendre symbol

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Richard E Borcherds 53 tutorials here
Mathematics

This lecture is part 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

We use Gauss’s lemma to find out when -2, 3, 5, are quadratic residues of a prime and give some applications.

The textbook is “An introduction to the theory of numbers” by Niven, Zuckerman, and Montgomery (5th edition).