In case it helps, I found this course useful as intro to elliptical curve crypto - https://youtube.com/@introductiontocryptography4223?si=O-5_a... lectures 16 and 17 in particular.

Seems like they used to. Just tried to register out of state as an adult and got this -

As of July 15, 2022, BPL is no longer offering out of state memberships. BPL library cards remain free for anyone who lives, works, pays property taxes or attends school in New York State.

> For a limited time

April 13 to July 15, 2022. 93 days.