关于质因子，望NN们解答！！！万分感谢！！

lohashilda

这周五就要上考场了，今天做Prep模考，其中有一题数学做错，看了答案也不知从何下手，恳请NN们帮忙解答，题目如下：
For every positive even integer n, the function h(n) is defined to be the product of all the even integers from 2 to n, inclusive. If p is the smallest prime factor of h(100)+1, then p is


A. between 2 and 10
B. between 10 and 20

C. between 20 and 30
D. between 30 and 40
E. greater than 40.


答案是E，望NN们解答

fatmoe

我觉得就是f(100)除p余数是p-1，所以50以内的质数就都不行了，所以肯定也是大于40的

lohashilda

自己顶一下下。。希望有人能看到><