49 lines
999 B
Markdown
49 lines
999 B
Markdown
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---
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id: 5900f5481000cf542c51005a
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title: 'Problem 475: Music festival'
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challengeType: 5
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forumTopicId: 302152
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dashedName: problem-475-music-festival
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---
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# --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 $f(24)\bmod 1\\,000\\,000\\,007 = 509\\,089\\,824$.
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Find $f(600)\bmod 1\\,000\\,000\\,007$.
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# --hints--
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`musicFestival()` should return `75780067`.
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```js
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assert.strictEqual(musicFestival(), 75780067);
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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 musicFestival() {
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return true;
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}
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musicFestival();
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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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