How Infinite Series Reveal the Unity of Mathematics

For sheer brilliance, it was hard to beat John von Neumann. An architect of the modern computer and inventor of game theory, von Neumann was legendary, above all, for his lightning-fast mental calculations. The story goes that one day somebody challenged him with a puzzle. Two bicyclists start at opposite ends of a road 20 miles long. Each cyclist travels toward the other at 10 miles per hour.

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