71 lines
961 B
Markdown
71 lines
961 B
Markdown
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---
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id: 5900f5271000cf542c51003a
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challengeType: 5
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title: 'Problem 443: GCD sequence'
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forumTopicId: 302115
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---
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## Description
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<section id='description'>
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Let g(n) be a sequence defined as follows:
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g(4) = 13,
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g(n) = g(n-1) + gcd(n, g(n-1)) for n > 4.
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The first few values are:
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n 4567891011121314151617181920...
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g(n) 1314161718272829303132333451545560...
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<!-- TODO Use MathJax -->
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You are given that g(1 000) = 2524 and g(1 000 000) = 2624152.
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Find g(1015).
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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>euler443()</code> should return 2744233049300770.
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testString: assert.strictEqual(euler443(), 2744233049300770);
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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 euler443() {
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return true;
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}
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euler443();
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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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