---
tag: 0WKG15TV3G
kind: concept
name: Fermat number
msc: [11A41]
sources:
  - url: https://en.wikipedia.org/wiki/Fermat_number
    locator: lead section
same_as:
  wikidata: Q207264
  wikipedia: Fermat number
---

## Summary

A Fermat number is an integer of the form $2^{2^n} + 1$ for a natural number $n$.
The [[definition of a Fermat number|0R03B54V4Z]] gives the precise form.