43 lines
		
	
	
		
			961 B
		
	
	
	
		
			Markdown
		
	
	
	
	
	
			
		
		
	
	
			43 lines
		
	
	
		
			961 B
		
	
	
	
		
			Markdown
		
	
	
	
	
	
| ---
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| id: 5900f4041000cf542c50ff17
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| title: 'Problem 152: Writing one half as a sum of inverse squares'
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| challengeType: 5
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| forumTopicId: 301783
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| dashedName: problem-152-writing-one-half-as-a-sum-of-inverse-squares
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| ---
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| 
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| # --description--
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| 
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| There are several ways to write the number 1/2 as a sum of inverse squares using distinct integers.
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| 
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| For instance, the numbers {2,3,4,5,7,12,15,20,28,35} can be used:
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| 
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| 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?
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| 
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| # --hints--
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| 
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| `euler152()` should return 301.
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| 
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| ```js
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| assert.strictEqual(euler152(), 301);
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| ```
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| 
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| # --seed--
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| 
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| ## --seed-contents--
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| 
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| ```js
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| function euler152() {
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| 
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|   return true;
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| }
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| 
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| euler152();
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| ```
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| 
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| # --solutions--
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| 
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| ```js
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| // solution required
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| ```
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