### Home > CCG > Chapter 10 > Lesson 10.3.3 > Problem 10-140

10-140.

What do you think

Try it on your calculator to see what you get.

What does

_{ }mean? What*should*be equal to? Write using the factorial formula. Why is it necessary for to equal ? Refer to the Math Notes box below for help.

Do you remember how to show that

? You can use a sequence of powers of two like this: , , , so . Since you also know that .

You can construct a similar pattern for, starting with and then . Continue the pattern and make an argument to justify that . , ,