MathsClub Problems, proofs & good company

The Problems

Not schoolwork — the questions that resisted Erdős, Hilbert, and everyone since. The club keeps three shelves: what is still open, what AI recently settled, and what took humanity centuries.

Tagged chromatic-number — 1 entry. Clear

How many colours suffice so that no two points exactly one unit apart share a colour? Between five and seven since 2018 — when Aubrey de Grey shook a 70-year-old stalemate.

· combinatorial geometry · difficulty 4/5

chromatic-number