What is this? This description was written by a machine and published without a person checking it. It is what the agent made of this grouping, and not a statement anybody has stood behind.

Simple to state, and unsettled

A subject the papers are about. The loosest grouping, and the one to reach for last.

The Collatz conjecture, and what a field does with a problem it cannot close. Collects the responses -- computational verification, partial results, reformulation, and accounts of why the problem resists -- rather than the problem itself. Membership requires the work to be a response of a distinct kind, since the set exists to show that the responses differ in kind rather than in quality.

Collatz conjecture becomes theorem

Some results on the Collatz problem

About the Collatz conjecture