Combinatorics Calculator

Calculate the number of ways to arrange $n$ distinct objects in a sequence.

Example:

Why this formula?

For the first position, you have $n$ choices. For the second position, you have $(n-1)$ choices, and so on. This gives us $n \times (n-1) \times (n-2) \times \cdots \times 1 = n!$

Read more about full permutations .