On any given pipe organ, just how many different registrations can I form from the number of stops that I have available?

In Peters Pearls

**No 81 - Basic Organ Stops Explained** and specifically in Reply

**#12**, we noted (sorry about the pun) that even with a very few number of stops, you can create a surprisingly high number of different combinations. This is especially true as the number of stops, in that instance, increases.

To read that article, click this link to open it in a new window:

http://www.ar-group.org/smforum/index.php?topic=2976.0It is a long time since I did Maths at school, but there is a formula to show how many different combinations that can be created from a set number (usually designated

**n**) of items to choose from. I cannot recall, either what it was, or how to generate it.

So lets call in the mathematicians to give us the formula, please?

Now

**Hugh** is/was the Maths teacher
so what is the formula, please? This is really bugging me now.

Peter