Hi Yongcheng,
I don't understand Case 1 of example 20 on page 20 of book 3 in Chapter 26. Could you please explain it in more details? I thought that the two configurations were the same because they could be rotated to look like each other and if that's right, there should only be one configuration which would be 210 ways to color.
Example 20: Each of four faces of a regular tetrahedron is colored one of 10 colors. How many distinct ways are there to color the tetrahedron? (Two colorings are considered distinct if they cannot be rotated to look like each other).
Thanks!!!
lele_2013
