lecture 17 - second half

We spent some time studying the recursive solution to the Tower of Hanoi problem. This is a key problem in understanding recursion, which will be a very useful technique in writing program. Then we show how to compute a closed form formula for some recursion. We show the steps to compute the solution, but did not go into the details of the proofs of why this method works. This method is easy to use, and for those who are interested in the proofs, all the details are provided in the textbook. This is the last lecture on counting. Once again let me emphasize that recursion is an important topic that we should know.