Problem: How many colors are needed so that if each point in the plane is assigned one of the colors, no two points which are exactly distance 1 apart will be assigned the same color? This problem has ...

This is a preview. Log in through your library . Journal Information The Mathematical Gazette is the original journal of the Mathematical Association and it is now over a century old. Its readership ...

Aubrey de Grey present a family of finite unit-distance graphs in the plane that are not 4-colorable, thereby improving the lower bound of the HadwigerNelson problem. The smallest such graph that we ...

An amateur mathematician just partially solved a problem that has vexed mathematicians since 1950. Science history: Russian mathematician quietly publishes paper — and solves one of the most famous ...

In 1950 Edward Nelson, then a student at the University of Chicago, asked the kind of deceptively simple question that can give mathematicians fits for decades. Imagine, he said, a graph—a collection ...