Permutation

An arrangment of the order of a Set

A permutation is an Isomorphism of a set

Partial Permutation

Repetitious Permutation

Multiset Permutation

The formula to find the number of distinct arrangements of a set of objects, some of which are indistinguishable where is the count of items where each is the number of repetitions of an object

For example, How many distinct arrangements can be made using the letters in the word: BANANA?

Solution

• Pretend like there are no duplicate letters: arrangements
• Of those arrangements some will be exactly the same Consider BANANA. We want to elimate the repeated arrangements How many ways can you arrange 3 As? How many ways can you arrange 2 Ns?