Exclamation Mark Symbol
The exclamation mark is used to represent the unary factorial operator. The factorial operator is used in calculating the number of combinations and permutations of a set or number of items.
Format  Display  Data 

Image  Download SVG ↓  
TeX 


Unicode  ! 

Usage
Combination  Formula
The combination formula describes the possible combinations of r elements out of a group of n elements where order does not matter.
Permutation  Formula
The permutation formula describes the possible permutations of r elements out of a group of n elements where order does matter.
Permutations of Set  Formula
The number of permutations of n distinct items is given by n factorial. A permutation is a unique ordering or arangment of the set of items.
Factorial  Notation
The exclamation mark is used to represent the factorial of a number in mathematics. A factorial is a unary operator.