47 lines
817 B
Markdown
47 lines
817 B
Markdown
---
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id: 5900f4fd1000cf542c51000f
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title: 'Problem 401: Sum of squares of divisors'
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challengeType: 5
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forumTopicId: 302069
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dashedName: problem-401-sum-of-squares-of-divisors
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---
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# --description--
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The divisors of 6 are 1,2,3 and 6.
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The sum of the squares of these numbers is 1+4+9+36=50.
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Let sigma2(n) represent the sum of the squares of the divisors of n. Thus sigma2(6)=50.
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Let SIGMA2 represent the summatory function of sigma2, that is SIGMA2(n)=∑sigma2(i) for i=1 to n. The first 6 values of SIGMA2 are: 1,6,16,37,63 and 113.
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Find SIGMA2(1015) modulo 109.
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# --hints--
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`euler401()` should return 281632621.
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```js
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assert.strictEqual(euler401(), 281632621);
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```
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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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# --solutions--
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```js
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// solution required
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```
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