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In three new variations of a famous logic puzzle, what are the best strategies for guessing the color of the hat on your head?

At 86, Britain’s preeminent mathematical matchmaker is still tackling the big questions and dreaming of a union between the quantum and the gravitational forces.

Assigning elements from a large collection to one of two categories can yield almost “magical” predictions about highly complicated problems without actually solving them.

In a geometrically designed social club, how do dancing, triangles and hexagons mix?

The solution to this month’s puzzle gets to the bottom of the famously ambiguous Sleeping Beauty probability problem.

Like a visually ambiguous Necker cube, the famous Sleeping Beauty problem can be perceived in two seemingly valid ways.

The solution to this month’s puzzle explains how to design a Sudoku square to figure out the likes and dislikes of four or eight finicky friends.

Three years ago, a solitary mathematician released an impenetrable proof of the famous *abc* conjecture. At a recent conference dedicated to the work, optimism mixed with bafflement.

Computer scientists are abuzz over a fast new algorithm for solving one of the central problems in the field.