56 lines
		
	
	
		
			1.3 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
		
		
			
		
	
	
			56 lines
		
	
	
		
			1.3 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
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								---
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								id: 5900f4141000cf542c50ff26
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								challengeType: 5
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								title: 'Problem 167: Investigating Ulam sequences'
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								videoUrl: ''
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								localeTitle: 问题167:研究Ulam序列
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								---
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								## Description
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								<section id="description">对于两个正整数a和b,Ulam序列U(a,b)由U(a,b)1 = a,U(a,b)2 = b定义,对于k> 2,U(a,b) )k是大于U(a,b)(k-1)的最小整数,它可以用一种方式写成U(a,b)的两个不同的先前成员的总和。例如,序列U(1,2)以1,2,3 = 1 + 2,4 = 1 + 3,6 = 2 + 4,8 = 2 + 6,11 = 3 + 8开始; 5不属于它,因为5 = 1 + 4 = 2 + 3有两个表示作为前两个成员的总和,同样7 = 1 + 6 = 3 + 4.找到ΣU(2,2n + 1)k为2≤n≤10,其中k = 1011。 </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>euler167()</code>应该返回3916160068885。
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								    testString: 'assert.strictEqual(euler167(), 3916160068885, "<code>euler167()</code> should return 3916160068885.");'
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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 euler167() {
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								  // Good luck!
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								  return true;
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								}
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								euler167();
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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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