---
tag: 0Z0NE3J6JX
kind: concept
name: Pell's equation
msc: [11D09]
sources:
  - url: https://en.wikipedia.org/wiki/Pell%27s_equation
    locator: lead section
same_as:
  wikidata: Q853067
  wikipedia: Pell's equation
---

## Summary

Pell's equation is the Diophantine equation $x^2 - d y^2 = 1$, where $d$ is a positive integer that is not a perfect square.
The [[definition of Pell's equation|0AF3DANJ76]] gives the precise form.