56 lines
		
	
	
		
			1.4 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
		
		
			
		
	
	
			56 lines
		
	
	
		
			1.4 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
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								---
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								id: 5900f53d1000cf542c51004f
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								challengeType: 5
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								title: 'Problem 464: Möbius function and intervals'
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								videoUrl: ''
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								localeTitle: 问题464:莫比乌斯函数和区间
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								---
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								## Description
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								<section id="description"> Möbius函数,表示为μ(n),定义为:μ(n)=( -  1)ω(n),如果n是无平方(其中ω(n)是n的不同素因子的数量)μ(n) )如果n不是无平方,则= 0。 <p>令P(a,b)为区间[a,b]中的整数n,使得μ(n)= 1.设N(a,b)为区间[a,b]中的整数n这样μ(n)= -1。例如,P(2,10)= 2且N(2,10)= 4。 </p><p>令C(n)为整数对(a,b)的数目,使得:1≤a≤b≤n,99·N(a,b)≤100·P(a,b),和99·P( a,b)≤100·N(a,b)。 </p><p>例如,C(10)= 13,C(500)= 16676和C(10000)= 20155319。 </p><p>找C(2 000 000)。 </p></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>euler464()</code>应返回198775297232878。
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								    testString: 'assert.strictEqual(euler464(), 198775297232878, "<code>euler464()</code> should return 198775297232878.");'
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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 euler464() {
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								  // Good luck!
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								  return true;
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								}
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								euler464();
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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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