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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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											2019-08-05 09:17:33 -07:00
										 
									 
								 
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								forumTopicId: 302152
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											2021-01-13 03:31:00 +01:00
										 
									 
								 
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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. 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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								# --hints--
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								`euler475()` should return 75780067.
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											2020-11-27 19:02:05 +01:00
										 
									 
								 
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								```js
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								assert.strictEqual(euler475(), 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 euler475() {
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								  return true;
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								}
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								euler475();
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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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