72 lines
1.1 KiB
Markdown
72 lines
1.1 KiB
Markdown
---
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id: 5900f4d61000cf542c50ffe9
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challengeType: 5
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title: 'Problem 362: Squarefree factors'
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---
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## Description
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<section id='description'>
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Consider the number 54.
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54 can be factored in 7 distinct ways into one or more factors larger than 1:
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54, 2×27, 3×18, 6×9, 3×3×6, 2×3×9 and 2×3×3×3.
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If we require that the factors are all squarefree only two ways remain: 3×3×6 and 2×3×3×3.
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Let's call Fsf(n) the number of ways n can be factored into one or more squarefree factors larger than 1, so
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Fsf(54)=2.
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Let S(n) be ∑Fsf(k) for k=2 to n.
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S(100)=193.
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Find S(10 000 000 000).
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</section>
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## Instructions
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<section id='instructions'>
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</section>
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## Tests
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<section id='tests'>
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```yml
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tests:
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- text: <code>euler362()</code> should return 457895958010.
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testString: assert.strictEqual(euler362(), 457895958010, '<code>euler362()</code> should return 457895958010.');
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```
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</section>
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## Challenge Seed
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<section id='challengeSeed'>
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<div id='js-seed'>
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```js
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function euler362() {
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// Good luck!
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return true;
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}
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euler362();
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```
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</div>
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</section>
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## Solution
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<section id='solution'>
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```js
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// solution required
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```
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</section>
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