56 lines
		
	
	
		
			1.1 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
		
		
			
		
	
	
			56 lines
		
	
	
		
			1.1 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
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								id: 5900f4be1000cf542c50ffd0
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								challengeType: 5
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								title: 'Problem 337: Totient Stairstep Sequences'
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								videoUrl: ''
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								localeTitle: 问题337欧拉序列阶梯
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								---
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								## Description
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								<section id="description">令{a1,a2,...,an}为长度为n的整数序列,使得:a1 = 6,对于所有1≤i<n:φ(ai)<φ(ai + 1)<ai <ai + 11令S(N)为具有≤N的这种序列的数目。例如,S(10)= 4:{6},{6,8},{6,8,9}和{6,10}。我们可以验证S(100)= 482073668和S(10 000)mod 108 = 73808307。 <p>找到S(20 000 000)mod 108。 </p><p> 1φ表示欧拉的函数。 </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>euler337()</code>应该返回85068035。
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								    testString: 'assert.strictEqual(euler337(), 85068035, "<code>euler337()</code> should return 85068035.");'
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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 euler337() {
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								  // Good luck!
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								  return true;
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								}
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								euler337();
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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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