IMC 2020 · Problem 8

Day 227th IMC · Online

Statement

Compute

lim⁡n→∞1log⁡log⁡n∑k=1n(−1)k(nk)log⁡k.\lim_{n \to \infty} \frac{1}{\log\log n} \sum_{k=1}^{n} (-1)^k \binom{n}{k} \log k.

(Here log⁡\log denotes the natural logarithm.)

Official solution

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