---
id: 5900f5001000cf542c510012
challengeType: 5
title: 'Problem 404: Crisscross Ellipses'
---
## Description
Ea is an ellipse with an equation of the form x2 + 4y2 = 4a2.
Ea' is the rotated image of Ea by θ degrees counterclockwise around the origin O(0, 0) for 0° < θ < 90°.
b is the distance to the origin of the two intersection points closest to the origin and c is the distance of the two other intersection points.
We call an ordered triplet (a, b, c) a canonical ellipsoidal triplet if a, b and c are positive integers.
For example, (209, 247, 286) is a canonical ellipsoidal triplet.
Let C(N) be the number of distinct canonical ellipsoidal triplets (a, b, c) for a ≤ N.
It can be verified that C(103) = 7, C(104) = 106 and C(106) = 11845.
Find C(1017).
## Instructions
## Tests
```yml
tests:
- text: euler404() should return 1199215615081353.
testString: assert.strictEqual(euler404(), 1199215615081353, 'euler404() should return 1199215615081353.');
```
## Challenge Seed
```js
function euler404() {
// Good luck!
return true;
}
euler404();
```