HMMT 二月 2006 · 冲刺赛 · 第 14 题
HMMT February 2006 — Guts Round — Problem 14
题目详情
- [7] Let X be as in problem 13. Let Y be the number of ways to order X crimson flowers, X scarlet flowers, and X vermillion flowers in a row so that no two flowers of the same hue are adjacent. (Flowers of the same hue are mutually indistinguishable.) Find Y . √
解析
- Let X be as in problem 13. Let Y be the number of ways to order X crimson flowers, X scarlet flowers, and X vermillion flowers in a row so that no two flowers of the same hue are adjacent. (Flowers of the same hue are mutually indistinguishable.) Find Y . Answer: 30 Solution: Problems 13–15 go together. See below. √