| 查看: 124 | 回复: 0 | |||
| 当前主题已经存档。 | |||
[交流]
【求助】求解几个组合数学的习题.
|
|||
|
1. Show that if 100 integers are chosen from 1,2,...,200,and one of the integers chosen is less than 16,then there are two chosen numbers such that one of them is divisible by the other. 2. Use the pigeonhole principle to prove that the decimal expansion of a rational number m/n eventually is repeating. For example, 34,478/99,900=0.34512512512512512... 3. Suppose that the mn people of a marching band are standing in a rectangular formation of m rows and n columns in such a way that in each row each person is taller than the one to her or his left. Suppose that the leader rearrange the people in each column in increasing order of height from front to back. Show that the rows are still arranged in increasing order of height from left to right. 4. A collection of subsets of {1,2,...,n} has the property that each pair of subsets has at least one element in common.Porve that there are at most 2 的n-1次方 subsets in the collection. 5. Let s be a set of 6 points in the plane, with no 3 of the points collinear. Color either red or blue each of the 15 line segments determined by the points of s.Show that there are at least two triangles determined by points of s which are either red triangles or blue triangles.(Both may be red ,or both may be blue,or one may be red and the other blue) 以上习题来自"组合数学"(第四版) 谢谢.  |
回复此楼» 猜你喜欢
孩子确诊有中度注意力缺陷
已经有14人回复
-
三甲基碘化亚砜的氧化反应
已经有4人回复
-
请问下大家为什么这个铃木偶联几乎不反应呢
已经有5人回复
-
请问有评职称，把科研教学业绩算分排序的高校吗
已经有5人回复
-
2025冷门绝学什么时候出结果
已经有3人回复
-
天津工业大学郑柳春团队欢迎化学化工、高分子化学或有机合成方向的博士生和硕士生加入
已经有4人回复
-
康复大学泰山学者周祺惠团队招收博士研究生
已经有6人回复
-
AI论文写作工具：是科研加速器还是学术作弊器？
已经有3人回复
-
论文投稿，期刊推荐
已经有4人回复
-
请问2026国家基金面上项目会启动申2停1吗
已经有5人回复
