Probability & Combinatorics
Basic

Factorial

Product of all positive integers up to n.

Formula

n!=n×(n−1)×⋯×2×1n! = n \times (n-1) \times \cdots \times 2 \times 1

Variables

nNon-negative integer

Example

5! = 120

Did You Know?

By convention 0! = 1, which makes many formulae consistent.

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