83 lines
		
	
	
		
			972 B
		
	
	
	
		
			Markdown
		
	
	
	
	
	
		
		
			
		
	
	
			83 lines
		
	
	
		
			972 B
		
	
	
	
		
			Markdown
		
	
	
	
	
	
|   | --- | ||
|  | id: 5900f4091000cf542c50ff1c | ||
|  | title: 'Problem 157: Solving the diophantine equation' | ||
|  | challengeType: 5 | ||
|  | forumTopicId: 301788 | ||
|  | dashedName: problem-157-solving-the-diophantine-equation | ||
|  | --- | ||
|  | 
 | ||
|  | # --description--
 | ||
|  | 
 | ||
|  | Consider the diophantine equation 1/a+1/b= p/10n with a, b, p, n positive integers and a ≤ b. | ||
|  | 
 | ||
|  | For n=1 this equation has 20 solutions that are listed below: | ||
|  | 
 | ||
|  | 1/1+1/1=20/10 | ||
|  | 
 | ||
|  | 1/1+1/2=15/10 | ||
|  | 
 | ||
|  | 1/1+1/5=12/10 | ||
|  | 
 | ||
|  | 1/1+1/10=11/10 | ||
|  | 
 | ||
|  | 1/2+1/2=10/10 | ||
|  | 
 | ||
|  | 1/2+1/5=7/10 | ||
|  | 
 | ||
|  | 1/2+1/10=6/10 | ||
|  | 
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|  | 1/3+1/6=5/10 | ||
|  | 
 | ||
|  | 1/3+1/15=4/10 | ||
|  | 
 | ||
|  | 1/4+1/4=5/10 | ||
|  | 
 | ||
|  | 1/4+1/20=3/10 | ||
|  | 
 | ||
|  | 1/5+1/5=4/10 | ||
|  | 
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|  | 1/5+1/10=3/10 | ||
|  | 
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|  | 1/6+1/30=2/10 | ||
|  | 
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|  | 1/10+1/10=2/10 | ||
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|  | 1/11+1/110=1/10 | ||
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|  | 1/12+1/60=1/10 | ||
|  | 
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|  | 1/14+1/35=1/10 | ||
|  | 
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|  | 1/15+1/30=1/10 | ||
|  | 
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|  | 1/20+1/20=1/10 | ||
|  | 
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|  | How many solutions has this equation for 1 ≤ n ≤ 9? | ||
|  | 
 | ||
|  | # --hints--
 | ||
|  | 
 | ||
|  | `euler157()` should return 53490. | ||
|  | 
 | ||
|  | ```js | ||
|  | assert.strictEqual(euler157(), 53490); | ||
|  | ``` | ||
|  | 
 | ||
|  | # --seed--
 | ||
|  | 
 | ||
|  | ## --seed-contents--
 | ||
|  | 
 | ||
|  | ```js | ||
|  | function euler157() { | ||
|  | 
 | ||
|  |   return true; | ||
|  | } | ||
|  | 
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|  | euler157(); | ||
|  | ``` | ||
|  | 
 | ||
|  | # --solutions--
 | ||
|  | 
 | ||
|  | ```js | ||
|  | // solution required | ||
|  | ``` |