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 dynamical-systems — 1 entry. Clear

Take any positive integer: halve it if even, else triple it and add one. Does the sequence always reach 1?

Posed by Lothar Collatz · 1937 · dynamical systems / number theory · difficulty 5/5

dynamical-systems