The last IMO problem AI could not solve

A beautiful puzzle that eluded AI, and the intuition it requires. Check out our virtual career fair: https://3b1b.co/talent See new videos early: https://3b1b.co/support An equally valuable form of support is to simply share the videos. Home page: https://www.3blue1brown.com Guest post I referenced on Terry Tao's blog: https://terrytao.wordpress.com/2026/09/18/if-math-is-more-than-proof-we-need-to-better-celebrate-the-rest-of-it/ Evan Chen also wrote up nice solution notes for this problem, along with all the others on that year's test. https://web.evanchen.cc/exams/IMO-2025-notes.pdf The chan