2018-10-10 22:03:03 +00:00
|
|
|
|
---
|
|
|
|
|
id: 5900f5001000cf542c510012
|
|
|
|
|
challengeType: 5
|
|
|
|
|
videoUrl: ''
|
2020-10-01 15:54:21 +00:00
|
|
|
|
title: 问题404:交叉椭圆
|
2018-10-10 22:03:03 +00:00
|
|
|
|
---
|
|
|
|
|
|
|
|
|
|
## Description
|
|
|
|
|
<section id="description"> Ea是椭圆,其形式为x2 + 4y2 = 4a2。 Ea'是Ea的旋转图像,绕原点O(0,0)逆时针旋转θ度0°<θ<90°。 <p> b是距离原点最近的两个交点的原点的距离,c是另外两个交点的距离。如果a,b和c是正整数,我们称有序三元组(a,b,c)为规范椭圆体三元组。例如,(209,247,286)是规范的椭圆体三重态。 </p><p>令C(N)为a≤N的不同规范椭球三胞胎(a,b,c)的数量。可以证实C(103)= 7,C(104)= 106和C(106)= 11845 。 </p><p>找到C(1017)。 </p></section>
|
|
|
|
|
|
|
|
|
|
## Instructions
|
|
|
|
|
<section id="instructions">
|
|
|
|
|
</section>
|
|
|
|
|
|
|
|
|
|
## Tests
|
|
|
|
|
<section id='tests'>
|
|
|
|
|
|
|
|
|
|
```yml
|
|
|
|
|
tests:
|
|
|
|
|
- text: <code>euler404()</code>应该返回1199215615081353。
|
2020-02-17 16:40:55 +00:00
|
|
|
|
testString: assert.strictEqual(euler404(), 1199215615081353);
|
2018-10-10 22:03:03 +00:00
|
|
|
|
|
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
</section>
|
|
|
|
|
|
|
|
|
|
## Challenge Seed
|
|
|
|
|
<section id='challengeSeed'>
|
|
|
|
|
|
|
|
|
|
<div id='js-seed'>
|
|
|
|
|
|
|
|
|
|
```js
|
|
|
|
|
function euler404() {
|
|
|
|
|
// Good luck!
|
|
|
|
|
return true;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
euler404();
|
|
|
|
|
|
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
</div>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
</section>
|
|
|
|
|
|
|
|
|
|
## Solution
|
|
|
|
|
<section id='solution'>
|
|
|
|
|
|
|
|
|
|
```js
|
|
|
|
|
// solution required
|
|
|
|
|
```
|
2020-08-13 15:24:35 +00:00
|
|
|
|
|
|
|
|
|
/section>
|