2018-10-10 18:03:03 -04:00
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---
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id: 5900f54b1000cf542c51005d
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2020-12-16 00:37:30 -07:00
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title: 问题479:崛起的根源
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2018-10-10 18:03:03 -04:00
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challengeType: 5
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videoUrl: ''
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2021-01-13 03:31:00 +01:00
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dashedName: problem-479-roots-on-the-rise
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2018-10-10 18:03:03 -04:00
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---
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2020-12-16 00:37:30 -07:00
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# --description--
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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设ak,bk和ck表示表达式1 / x =(k / x)2(k + x2)-kx的三个解(实数或复数)。
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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例如,对于k = 5,我们看到{a5,b5,c5}约为{5.727244,-0.363622 + 2.057397i,-0.363622-2.057397i}。
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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令所有整数p,k的S(n)=Σ(ak + bk)p(bk + ck)p(ck + ak)p,使得1≤p,k≤n。
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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有趣的是,S(n)总是一个整数。例如,S(4)= 51160。
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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求S(106)modulo 1 000 000 007。
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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# --hints--
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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`euler479()`应该返回191541795。
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2018-10-10 18:03:03 -04:00
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```js
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2020-12-16 00:37:30 -07:00
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assert.strictEqual(euler479(), 191541795);
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2018-10-10 18:03:03 -04:00
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```
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2021-01-13 03:31:00 +01:00
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# --seed--
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## --seed-contents--
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```js
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function euler479() {
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return true;
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}
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euler479();
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```
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2020-12-16 00:37:30 -07:00
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# --solutions--
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2020-08-13 17:24:35 +02:00
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2021-01-13 03:31:00 +01:00
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```js
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// solution required
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```
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