The last day of Ramsey theorey was (still) awesome.

In additive combinatorics today, we proved the hardest problem from this year’s IMC, which the professor didn’t even know had been used at the IMC. It’s apparently a fairly well-known result, although not well-known enough for anyone at the IMC to have seen. If the IMC had been a few weeks later, though….

(That problem, unlike two problems that on reflection were easier, I solved, and I didn’t need the time, so it’dn’t’ve mattered for me.)