2018-10-10 18:03:03 -04:00
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---
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id: 5900f4571000cf542c50ff6a
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2020-12-16 00:37:30 -07:00
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title: 问题235:算术几何序列
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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-235-an-arithmetic-geometric-sequence
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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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给定是算术几何序列u(k)=(900-3k)rk-1。设s(n)=Σk= 1 ... nu(k)。
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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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找到r的值,其中s(5000)= - 600,000,000,000。
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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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将您的答案四舍五入到小数点后面的12位。
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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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`euler235()`应该返回1.002322108633。
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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(euler235(), 1.002322108633);
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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 euler235() {
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return true;
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}
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euler235();
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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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