I wrote an ugly master's thesis in mathematics. There were errors and I think it is not worth publishing. However, I managed to prove one theorem in a simple way that I have never seen before. I have seen another proof of the theorem and, in my opinion, it is more complicated than my proof.
What would be a suitable way to get other mathematicians to know the proof?
Is it fine if I post a question to Mathematics Stack Exchange and answer my own question?