I love "Dissection puzzle" http://mathworld.wolfram.com/Dissection.html . And now, I found twitter's hashtag #christmath https://twitter.com/hashtag/christmath?f=tweets&vertical=default Thanks!
The patterns of "中村義作万能分割" https://twitter.com/wasanp_/status/961913371858579456 are about 4 cases as shown in the following picture. #Beautiful
A Mastodon instance for maths people. The kind of people who make \(\pi z^2 \times a\) jokes.
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