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MathNet 2018-part-01 — 181 problems (EN–VI) Question 113

Math Olympiad Vault · MathNet 2018-part-01 — 181 problems (EN–VI)

Question 113

For every integer $n \ge 2$ prove the inequality
$$
\frac{1}{2!} + \frac{2}{3!} + \dots + \frac{2^{n-2}}{n!} \le \frac{3}{2},
$$
where $k! = 1 \cdot 2 \cdot \dots \cdot k$.