拙文“简化杨辉三角”(见本刊1986年第九期)发表后,有同事向作者提出如果不只是考虑组合系数的“奇偶性”,而是考虑对其他自然数的同余性质,有没有办法?例如能否很快告知C_(255)~(130)的个位数是多少(即C_(255)~(130)(mod10)=?)。本文将讨论组合系数对素数的同余性质,并由此 After the publication of the “Simplified Yanghui Triangle” (see 1986 ninth issue of the Simplified Chinese Version), some colleagues suggested to the author that if it is not only to consider the “parity” of the combination coefficient, but to consider the congruence of other natural numbers, is there a way? For example, whether the single digits of C_(255)~(130) can be quickly notified (ie, C_(255)~(130)(mod10)=?). This article will discuss the congruence properties of the combination coefficients for prime numbers and thus