用DUG三模型计算满射的个数和等价关系的个数  

Calculate the Number of Surjections and Equivalent Relations using DUG Three Models

作　　者：姜保庆[1] JIANG Baoqing(School of Computer and Information Engineering,Henan University,Kaifeng 475004,China)

机构地区：[1]河南大学计算机与信息工程学院,河南开封475004

出　　处：《高等数学研究》2024年第4期95-97,121,共4页Studies in College Mathematics

摘　　要：本文利用DUG三模型给出了有限集之间满射个数和有限集上等价关系个数的简洁计算公式.给出了更一般球盒分配问题的DUG三模型计算公式.The number of surjections between finite sets and the number of equivalent relations on finite sets are simply calculated by DUG three models.Two simple calculation formulas are given.A more general ball-box assignment problem is calculated by DUG three models.

关 键 词：满射个数 等价关系个数 DUG三模型 U数 G数 

分 类 号：O158[理学—数学]