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							|  |  |  |  | id: 5900f4651000cf542c50ff77 | 
					
						
							|  |  |  |  | challengeType: 5 | 
					
						
							|  |  |  |  | title: 'Problem 248: Numbers for which Euler’s totient function equals 13!' | 
					
						
							|  |  |  |  | --- | 
					
						
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							|  |  |  |  | ## Description
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							|  |  |  |  | <section id='description'> | 
					
						
							|  |  |  |  | The first number n for which φ(n)=13! is 6227180929. | 
					
						
							|  |  |  |  | Find the 150,000th such number. | 
					
						
							|  |  |  |  | </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: | 
					
						
							|  |  |  |  |   - text: <code>euler248()</code> should return 23507044290. | 
					
						
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										 |  |  |  |     testString: assert.strictEqual(euler248(), 23507044290, '<code>euler248()</code> should return 23507044290.'); | 
					
						
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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 euler248() { | 
					
						
							|  |  |  |  |   // Good luck! | 
					
						
							|  |  |  |  |   return true; | 
					
						
							|  |  |  |  | } | 
					
						
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							|  |  |  |  | euler248(); | 
					
						
							|  |  |  |  | ``` | 
					
						
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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> |