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											2018-10-10 18:03:03 -04:00
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							|  |  |  |  | id: 5900f53d1000cf542c51004f | 
					
						
							|  |  |  |  | challengeType: 5 | 
					
						
							|  |  |  |  | title: 'Problem 464: Möbius function and intervals' | 
					
						
							|  |  |  |  | videoUrl: '' | 
					
						
							|  |  |  |  | localeTitle: 问题464:莫比乌斯函数和区间 | 
					
						
							|  |  |  |  | --- | 
					
						
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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"> | 
					
						
							|  |  |  |  | </section> | 
					
						
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							|  |  |  |  | ## Tests
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							|  |  |  |  | <section id='tests'> | 
					
						
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							|  |  |  |  | ```yml | 
					
						
							|  |  |  |  | tests: | 
					
						
							|  |  |  |  |   - text: <code>euler464()</code>应返回198775297232878。 | 
					
						
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										 |  |  |  |     testString: assert.strictEqual(euler464(), 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 | 
					
						
							|  |  |  |  | function euler464() { | 
					
						
							|  |  |  |  |   // Good luck! | 
					
						
							|  |  |  |  |   return true; | 
					
						
							|  |  |  |  | } | 
					
						
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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 | 
					
						
							|  |  |  |  | // solution required | 
					
						
							|  |  |  |  | ``` | 
					
						
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							|  |  |  |  | /section> |