2018-09-30 22:01:58 +00:00
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---
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id: 5900f5481000cf542c51005a
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challengeType: 5
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title: 'Problem 475: Music festival'
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---
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## Description
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<section id='description'>
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12n musicians participate at a music festival. On the first day, they form 3n quartets and practice all day.
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It is a disaster. At the end of the day, all musicians decide they will never again agree to play with any member of their quartet.
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On the second day, they form 4n trios, each musician avoiding his previous quartet partners.
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Let f(12n) be the number of ways to organize the trios amongst the 12n musicians.
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You are given f(12) = 576 and f(24) mod 1 000 000 007 = 509089824.
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Find f(600) mod 1 000 000 007.
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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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2018-10-04 13:37:37 +00:00
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tests:
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- text: <code>euler475()</code> should return 75780067.
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2018-10-20 18:02:47 +00:00
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testString: assert.strictEqual(euler475(), 75780067, '<code>euler475()</code> should return 75780067.');
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2018-09-30 22:01:58 +00:00
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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 euler475() {
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// Good luck!
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return true;
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}
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euler475();
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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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