2018-10-10 22:03:03 +00:00
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---
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id: 5900f5261000cf542c510038
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2020-12-16 07:37:30 +00:00
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title: 问题441:互质夫妇的反向总和
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2018-10-10 22:03:03 +00:00
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challengeType: 5
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videoUrl: ''
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2021-01-13 02:31:00 +00:00
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dashedName: problem-441-the-inverse-summation-of-coprime-couples
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2018-10-10 22:03:03 +00:00
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---
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2020-12-16 07:37:30 +00:00
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# --description--
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2018-10-10 22:03:03 +00:00
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2020-12-16 07:37:30 +00:00
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对于整数M,我们将R(M)定义为满足所有这些条件的所有整数对p和q的1 /(p·q)之和:
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2018-10-10 22:03:03 +00:00
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2020-12-16 07:37:30 +00:00
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1≤p<q≤Mp +q≥Mp和q是互质的。
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2018-10-10 22:03:03 +00:00
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2020-12-16 07:37:30 +00:00
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我们还将S(N)定义为R(i)的总和为2≤i≤N。我们可以验证S(2)= R(2)= 1/2,S(10)≈6.9147和S(100) )≈58.2962。
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2018-10-10 22:03:03 +00:00
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2020-12-16 07:37:30 +00:00
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找到S(107)。将您的答案四舍五入到小数点后四位。
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2018-10-10 22:03:03 +00:00
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2020-12-16 07:37:30 +00:00
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# --hints--
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2018-10-10 22:03:03 +00:00
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2020-12-16 07:37:30 +00:00
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`euler441()`应返回5000088.8395。
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2018-10-10 22:03:03 +00:00
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```js
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2020-12-16 07:37:30 +00:00
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assert.strictEqual(euler441(), 5000088.8395);
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2018-10-10 22:03:03 +00:00
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```
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2021-01-13 02:31:00 +00:00
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# --seed--
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## --seed-contents--
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```js
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function euler441() {
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return true;
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}
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euler441();
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```
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2020-12-16 07:37:30 +00:00
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# --solutions--
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2020-08-13 15:24:35 +00:00
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2021-01-13 02:31:00 +00:00
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```js
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// solution required
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```
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