Infinite Sums which turn out to be Riemann Integrals

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I'm looking for examples of infinite series which look hard to evaluate at first, but become very simple when viewed as a Riemann integral. An example would be $$\frac{1}{n+1}+\frac{1}{n+2}+ \ldots +\frac{1}{2n}=\sum_{i=1}^{n}\frac{1}{n+i}\\=\frac{1}{n}\sum_{i=1}^{n}\frac{1}{1+i/n} \to \int_{0}^{1}\frac{1}{1+x}dx=\log 2$$ (I just think they're cute)