Math: Number of possible combinations when sorted alphabetically
Posted on 2014-02-03
I have 17 items:
I am working on a project that combines PDF documents in order, and I need to know how many total options would be possible.
There can be any combination of them, providing each item can only appear in the list once and the results are always in alphabetical order.
For example these would all be valid,
But these would not be valid:
How can the number of options be calculated?