@JordiGH That said, I can point to instances where I've added proofs I made up myself rather than finding proper source. E.g. I added the proof in https://en.wikipedia.org/wiki/F%C3%A1ry%27s_theorem in 2006, but the oldest published source I've found for that particular proof is dated 2010. Fortunately the 2010 source didn't credit Wikipedia for the proof (as that would have disqualified it as a source) Probably these days I would try to choose a simple published proof rather than rolling my own, to have something to cite.
A Mastodon instance for maths people. The kind of people who make \(\pi z^2 \times a\) jokes.
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