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The solution to this month’s puzzle examines the use of abstract probabilities as an antidote to real-world ignorance.

For more than 50 years, the mathematician Neil Sloane has curated the authoritative collection of interesting and important integer sequences.

How do you solve probability problems that appear to have more than one correct answer?

Computers can translate French and prove mathematical theorems. But can they make deep conceptual insights into the way the world works?

The counterintuitive solution to this month’s puzzle raises philosophical questions about randomness and information.

A 115-year effort to bridge the particle and fluid descriptions of nature has led mathematicians to an unexpected answer.

Quanta’s new puzzle column asks you to believe the seemingly impossible — that you can win at a number guessing game with absolutely no information.

Solve this variation of Thomas Kirkman’s famous 1850 puzzle by arranging girls in walking groups. And think fast — the clock is ticking.

A 150-year-old conundrum about how to group people has been solved, but many puzzles remain.