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							|  |  |  |  | id: 5900f5111000cf542c510023 | 
					
						
							|  |  |  |  | challengeType: 5 | 
					
						
							|  |  |  |  | title: 'Problem 420: 2x2 positive integer matrix' | 
					
						
							|  |  |  |  | videoUrl: '' | 
					
						
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										 |  |  |  | localeTitle: 问题420:2x2正整数矩阵 | 
					
						
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											2018-10-10 18:03:03 -04:00
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							|  |  |  |  | ## Description
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										 |  |  |  | <section id="description"> | 
					
						
							|  |  |  |  | 正整数矩阵是其元素均为正整数的矩阵。 | 
					
						
							|  |  |  |  | 一些正整数矩阵可以两种不同方式表示为正整数矩阵的平方。 这是一个例子: | 
					
						
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							|  |  |  |  | 我们将F(N)定义为迹线小于N的2x2正整数矩阵的数目,并且可以用两种不同的方式将其表示为正整数矩阵的平方。 | 
					
						
							|  |  |  |  | 我们可以验证F(50)= 7和F(1000)= 1019。 | 
					
						
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							|  |  |  |  | 找出F(107)。 | 
					
						
							|  |  |  |  | </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: | 
					
						
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										 |  |  |  |   - text: <code>euler420()</code>应该返回145159332。 | 
					
						
							|  |  |  |  |     testString: assert.strictEqual(euler420(), 145159332); | 
					
						
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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 euler420() { | 
					
						
							|  |  |  |  |   // Good luck! | 
					
						
							|  |  |  |  |   return true; | 
					
						
							|  |  |  |  | } | 
					
						
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							|  |  |  |  | euler420(); | 
					
						
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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> |