ILL 1966 Problem 30

Let $n$ be a positive integer, prove that :

(a) $\log_{10}(n + 1) > \frac{3}{10n} +\log_{10}n ;$

(b) $\log n! > \frac{3n}{10}\left( \frac 12+\frac 13 +\cdots +\frac 1n -1\right).$

Dataset text AoPS wiki problems. Quoted with source.

Solutions

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