Skip to content / Đến nội dung
ThichHocToan.com

MathNet 2023-part-02 — 191 problems (EN–VI) Question 47

Math Olympiad Vault · MathNet 2023-part-02 — 191 problems (EN–VI)

Question 47

Count the number of rearrangements $a_{1}, a_{2}, \ldots, a_{2023}$ of the sequence $1,2, \ldots, 2023$ such that $a_{k} \gt k$ for exactly one value of $k$.