This post is being continuously updated with a collection of good learning resources.

Last updated on 18th June 2022.

Legendre’s Symbol

A good video by Michael Penn showing proof of the Legendre’s Symbol: https://www.youtube.com/watch?v=eKjjAr4EvmU (and good backflip) that kept me interested throughout the entire video.

A challenge on CryptoHack uses Legendre’s Symbol and more to find the quadratic residue and calculate the square root.