[AlanYx]

IMO doesn't reuse problems, but Terence Tao has a Mastodon post where he explains that the first five (of six) problems are generally ones where existing techniques can be leveraged to get to the answer. The sixth problem requires considerable originality. Notably, both Gemini and OpenAI's model didn't get the sixth problem. Still quite an achievement though.

[apayan]

Do you have another source for that? I checked his Mastodon feed and don't see any mention about the source of the questions from the IMO.

https://mathstodon.xyz/@tao

[Davidzheng]

strange statement--it's not true in general for sure (3&6 typically hardest but they certainly aren't fundamentally of a different nature to other questions) this year P6 seemed to be by far the hardest though but this posthoc statement should be read cautiously