Despite the greatest strides in mathematics, these hard math problems remain unsolved. Take a crack at them yourself.

Every mathematician has a story that goes something like this. You’re at a party, and someone asks what you do for a living. “I’m a mathematician,” you say. “You must be a genius!” they reply. Or ...

For all of the recent strides we’ve made in the math world, we’re forever crunching calculations in pursuit of deeper numerical knowledge. Some math problems have been challenging us for centuries—but ...