A "Venn diagram" with three overlapping circles is often used to illustrate the eight possible subsets associated with three given sets:
such as the image in http://robertdaylin.files.wordpress.com/2008/10/venn-diagram1.png.
Can the sixteen possibilities that arise with four given sets be illustrated by four overlapping circles?
I have no idea about this problem. Can anyone help me?
I have know the answer.But another problem come, what's the maximum number of regions with n overlapping circles?