I quite liked @ColinTheMathmo’s entry to #BigMathOff: a simple, initially counterintuitive result that becomes intuitively obvious after a quick think! I wonder how many totally different ways there are to prove it.
If you haven’t yet, go read about it and beautiful Penrose tilings: http://aperiodical.com/2018/07/the-big-internet-math-off-round-1-edmund-harriss-v-colin-wright/
A Mastodon instance for maths people. The kind of people who make \(\pi z^2 \times a\) jokes.
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