22afc2a0ca
Co-authored-by: Oliver Eyton-Williams <ojeytonwilliams@gmail.com> Co-authored-by: Kristofer Koishigawa <scissorsneedfoodtoo@gmail.com> Co-authored-by: Beau Carnes <beaucarnes@gmail.com>
67 lines
972 B
Markdown
67 lines
972 B
Markdown
---
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id: 5900f52c1000cf542c51003f
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challengeType: 5
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isHidden: false
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title: 'Problem 448: Average least common multiple'
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forumTopicId: 302120
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---
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## Description
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<section id='description'>
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The function lcm(a,b) denotes the least common multiple of a and b.
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Let A(n) be the average of the values of lcm(n,i) for 1≤i≤n.
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E.g: A(2)=(2+2)/2=2 and A(10)=(10+10+30+20+10+30+70+40+90+10)/10=32.
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Let S(n)=∑A(k) for 1≤k≤n.
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S(100)=122726.
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Find S(99999999019) mod 999999017.
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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>euler448()</code> should return 106467648.
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testString: assert.strictEqual(euler448(), 106467648);
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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 euler448() {
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// Good luck!
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return true;
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}
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euler448();
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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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