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											2018-09-30 23:01:58 +01:00
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							|  |  |  | id: 5900f54b1000cf542c51005d | 
					
						
							|  |  |  | challengeType: 5 | 
					
						
							|  |  |  | title: 'Problem 479: Roots on the Rise' | 
					
						
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							|  |  |  | ## Description
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							|  |  |  | <section id='description'> | 
					
						
							|  |  |  | Let ak, bk, and ck represent the three solutions (real or complex numbers) to the expression 1/x = (k/x)2(k+x2) - kx. | 
					
						
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							|  |  |  | For instance, for k = 5, we see that {a5, b5, c5} is approximately {5.727244, -0.363622+2.057397i, -0.363622-2.057397i}. | 
					
						
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										 |  |  | Let S(n) = Σ (ak+bk)p(bk+ck)p(ck+ak)p for all integers p, k such that 1 ≤ p, k ≤ n. | 
					
						
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							|  |  |  | Interestingly, S(n) is always an integer. For example, S(4) = 51160. | 
					
						
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							|  |  |  | Find S(106) modulo 1 000 000 007. | 
					
						
							|  |  |  | </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>euler479()</code> should return 191541795. | 
					
						
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										 |  |  |     testString: assert.strictEqual(euler479(), 191541795, '<code>euler479()</code> should return 191541795.'); | 
					
						
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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 euler479() { | 
					
						
							|  |  |  |   // Good luck! | 
					
						
							|  |  |  |   return true; | 
					
						
							|  |  |  | } | 
					
						
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							|  |  |  | euler479(); | 
					
						
							|  |  |  | ``` | 
					
						
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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 | 
					
						
							|  |  |  | ``` | 
					
						
							|  |  |  | </section> |