---
tag: 0XWG0JGDFW
kind: concept
name: Factorial
msc: [05A10]
sources:
  - url: https://en.wikipedia.org/wiki/Factorial
    locator: Definition
same_as:
  wikidata: Q120976
  wikipedia: Factorial
---

## Summary

The factorial of a natural number $n$ is the product of the positive integers up to $n$. It counts the orderings of $n$ distinct objects and appears in most counting formulas. The node [[factorial|0WFCGVMRRC]] gives the precise definition.