algèbre lycée recueilchapitre 1problème 1.2récurrence

A product of consecutive integers

Recueil COMIMa — Techniques de résolution de problèmes · 2026 · Madagascar · ★★★★★

Statement

Montrez que $(n+1)(n+2)\cdots 2n = 2^n \cdot 1 \cdot 3 \cdot 5 \cdot \cdots \cdot (2n-1)$ pour tout $n \in \mathbb{N}$.

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Origin : Recueil COMIMa — Techniques de résolution de problèmes · 2026 · Madagascar

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