数学理论与应用 ›› 2022, Vol. 42 ›› Issue (1): 85-91.

• • 上一篇    下一篇

一些二项式系数的最大公因数

肖嘉琪,袁平之*,林序灿   

  1. 华南师范大学数学科学学院,广州, 510631
  • 出版日期:2022-03-31 发布日期:2022-03-23

The Greatest Common Divisor of Certain Set of Binomial Coefficients

Xiao Jiaqi, Yuan Pingzhi*, Lin Xucan   

  1. School of Mathematical Science, South China Normal University, Guangzhou 510631, China
  • Online:2022-03-31 Published:2022-03-23
  • Contact: Pingzhi Yuan(1966-), Professor, PhD, E-mail: yuanpz@scnu.edu.cn
  • Supported by:
    This work is supported by National Natural Science Foundation of China (No. 12171163)

摘要:

本文证明: 若n4a0为整数且满足a<n3, 则

gcd({(nk):a<k<na})=n=pm+b(n,p), 0b(n,p)a,p,

其中 (nk)=n!k!(nk)!, 右边的连乘积遍历所有满足n=pm+b(n,p),mN0b(n,p)a 的素数 p.

作为上述结论的一个应用,我们回答洪[16]文中的一个问题.

关键词: 二项式系数 , 最大公因数

Abstract:

In this paper, we prove that if n4 and a0 are integers satisfying a<n3, then

gcd({(nk):a<k<na})=n=pm+b(n,p), 0b(n,p)a,p,

where (nk)=n!k!(nk)!, and the product in the right hand side runs through all primes p such that n=pm+b(n,p),mN and 0b(n,p)a.

As an application of our result, we give an answer to a problem in Hong [16].


Key words: Binomial coefficient , Greatest common divisor