43 lines
		
	
	
		
			961 B
		
	
	
	
		
			Markdown
		
	
	
	
	
	
		
		
			
		
	
	
			43 lines
		
	
	
		
			961 B
		
	
	
	
		
			Markdown
		
	
	
	
	
	
|   | --- | ||
|  | id: 5900f4041000cf542c50ff17 | ||
|  | title: 'Problem 152: Writing one half as a sum of inverse squares' | ||
|  | challengeType: 5 | ||
|  | forumTopicId: 301783 | ||
|  | dashedName: problem-152-writing-one-half-as-a-sum-of-inverse-squares | ||
|  | --- | ||
|  | 
 | ||
|  | # --description--
 | ||
|  | 
 | ||
|  | There are several ways to write the number 1/2 as a sum of inverse squares using distinct integers. | ||
|  | 
 | ||
|  | For instance, the numbers {2,3,4,5,7,12,15,20,28,35} can be used: | ||
|  | 
 | ||
|  | In fact, only using integers between 2 and 45 inclusive, there are exactly three ways to do it, the remaining two being: {2,3,4,6,7,9,10,20,28,35,36,45} and {2,3,4,6,7,9,12,15,28,30,35,36,45}. How many ways are there to write the number 1/2 as a sum of inverse squares using distinct integers between 2 and 80 inclusive? | ||
|  | 
 | ||
|  | # --hints--
 | ||
|  | 
 | ||
|  | `euler152()` should return 301. | ||
|  | 
 | ||
|  | ```js | ||
|  | assert.strictEqual(euler152(), 301); | ||
|  | ``` | ||
|  | 
 | ||
|  | # --seed--
 | ||
|  | 
 | ||
|  | ## --seed-contents--
 | ||
|  | 
 | ||
|  | ```js | ||
|  | function euler152() { | ||
|  | 
 | ||
|  |   return true; | ||
|  | } | ||
|  | 
 | ||
|  | euler152(); | ||
|  | ``` | ||
|  | 
 | ||
|  | # --solutions--
 | ||
|  | 
 | ||
|  | ```js | ||
|  | // solution required | ||
|  | ``` |