---
id: 5900f4551000cf542c50ff68
challengeType: 5
title: 'Problem 233: Lattice points on a circle'
---
## Description
Let f(N) be the number of points with integer coordinates that are on a circle passing through (0,0), (N,0),(0,N), and (N,N).
It can be shown that f(10000) = 36.
What is the sum of all positive integers N ≤ 1011 such that f(N) = 420 ?
## Instructions
## Tests
```yml
tests:
- text: euler233() should return 271204031455541300.
testString: assert.strictEqual(euler233(), 271204031455541300, 'euler233() should return 271204031455541300.');
```
## Challenge Seed
```js
function euler233() {
// Good luck!
return true;
}
euler233();
```