What are your favourite blogs / online lectures / other freely accessible resources on the mathematics behind cryptography, especially in the areas of number theory, elliptic curves, and quantum computing/algorithms?
I have extremely privileged access to a wealth of knowledge that is to others behind a very steep paywall. I recognise that and I would like my lectures to also link to more readily accessible resources.
@dequbed this is about discrete probability which I guess is at least one part of the math behind, I saw it mentioned in an intro lecture about cryptography: