47 lines
794 B
Markdown
47 lines
794 B
Markdown
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---
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id: 5900f5191000cf542c51002c
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title: 'Problem 429: Sum of squares of unitary divisors'
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challengeType: 5
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forumTopicId: 302099
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dashedName: problem-429-sum-of-squares-of-unitary-divisors
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---
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# --description--
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A unitary divisor d of a number n is a divisor of n that has the property gcd(d, n/d) = 1.
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The unitary divisors of 4! = 24 are 1, 3, 8 and 24.
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The sum of their squares is 12 + 32 + 82 + 242 = 650.
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Let S(n) represent the sum of the squares of the unitary divisors of n. Thus S(4!)=650.
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Find S(100 000 000!) modulo 1 000 000 009.
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# --hints--
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`euler429()` should return 98792821.
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```js
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assert.strictEqual(euler429(), 98792821);
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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 euler429() {
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return true;
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}
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euler429();
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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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