我觉得OLIVE MM的结论是以11一定在N集合里为假设得出来的,但是我们不知道N集合有什么组成,N集合可以一些非质数和一些质数但不包括11组成,这样11也不一定在阴影里亚?以下时OLIVEMM的解释.请帮忙看看,谢谢. 1)if m is non-prime, then 11 is not included, then 11 must in the shadow area of n; this is correct. but for 2), if all elements in n are odd, then 11 must in n, but this doesnot mean 11 must in or out of the shadowed area, i.e., if m is a set of all even numbers and prime numbers>2 and n is a set of all odd numbers>2, then 11 is in the overlaped area |