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Mathematics

Harmonic Series

Quick fact

The harmonic series is the most famous example of a divergent infinite series.

Why this is interesting

Did you know that adding up fractions like 1 + 1/2 + 1/3 + 1/4... can actually go on forever?

Read the full explanation

Understanding Harmonic Series

Imagine starting with 1, then adding half, then a third, then a quarter, and so on. Even though these numbers get smaller and smaller, they never add up to a finite number—they just keep growing, no matter how far you go.

A deeper explanation

The harmonic series is the sum of reciprocals of positive integers: 1 + 1/2 + 1/3 + 1/4 + ... This series diverges because, even though each term gets smaller, the partial sums grow without bound. It's a classic example used to show that not all infinite series converge, and it plays an important role in understanding convergence tests in calculus.

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