2018-10-10 22:03:03 +00:00
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---
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id: 5900f4fd1000cf542c51000f
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2020-12-16 07:37:30 +00:00
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title: 问题401:除数的平方和
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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-401-sum-of-squares-of-divisors
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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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6的除数是1,2,3和6.这些数的平方和是1 + 4 + 9 + 36 = 50。
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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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设sigma2(n)代表n的除数的平方和。因此sigma2(6)= 50。
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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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设SIGMA2表示sigma2的和函数,即对于i = 1到n,SIGMA2(n)=Σsigma2(i)。 SIGMA2的前6个值是:1,6,16,37,63和113。
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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SIGMA2(1015)modulo 109。
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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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`euler401()`应该返回281632621。
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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(euler401(), 281632621);
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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 euler401() {
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return true;
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}
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euler401();
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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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