> Also, have there been examples of researchers not affiliated with OpenAI (or another LLM creator), who have done something similar?

A couple small ones that I've seen (example here [0]), but not anything of the magnitude that OpenAI and Anthropic have put out. Likely just related to token limits.

> Another question I have is whether or not OpenAI 'simply' hired capable combinatorics researchers to work on problems, and they have, and the use of the model is incidental / secondary to their work.

I think their output has reached a level that precludes this possibility, but I of course don't have any hard proof.

[0]: https://www.reddit.com/r/math/comments/1uxj3cy/after_openais...