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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.

For this month’s puzzle, design a Sudoku square to figure out the likes and dislikes of four finicky friends.

The solution to this month’s puzzle explains how to find a rule behind a given sequence of numbers and challenges readers to take on a ‘lovely’ unsolved problem.

Can you infer the simple rule behind a number sequence that spikes up and down like the beating of a heart?

The solution to this month’s puzzle explains the artful mathematics behind symmetrical patterns.

Can you generate aesthetically pleasing, symmetrical curves with two numbers and a simple mathematical function?

The solution to this month’s puzzle uses both mathematics and psychology to explain trouble with choosing the fastest route.

When there are two paths to your destination, why does it always seem like you’re on the road with more traffic?