The SIGACT Committee for the Advancement of Theoretical Computer Science is planning a Wikipedia edit-a-thon, in Phoenix on June 24 as part of STOC: see https://thmatters.wordpress.com/2019/06/11/wikipedia-edit-a-thon-at-stoc19/
You can help, and you don't even have to brave the desert heat to do so! There's a shared spreadsheet linked from https://thmatters.wordpress.com/2017/05/02/tcs-wikipedia-project/ where CATCS is crowdsourcing TCS topics on Wikipedia that need help. Add your favorite missing algorithm, theorem, complexity class, etc, and it's likely it'll get some attention.
A Mastodon instance for maths people. The kind of people who make \(\pi z^2 \times a\) jokes.
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