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							|  |  |  |  | id: 5900f51e1000cf542c510030 | 
					
						
							|  |  |  |  | challengeType: 5 | 
					
						
							|  |  |  |  | title: 'Problem 432: Totient sum' | 
					
						
							|  |  |  |  | --- | 
					
						
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							|  |  |  |  | ## Description
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							|  |  |  |  | <section id='description'> | 
					
						
							|  |  |  |  | Let S(n,m) = ∑φ(n × i) for 1 ≤ i ≤ m. (φ is Euler's totient function) | 
					
						
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										 |  |  |  | You are given that S(510510,106 )= 45480596821125120. | 
					
						
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							|  |  |  |  | Find S(510510,1011). | 
					
						
							|  |  |  |  | Give the last 9 digits of your answer. | 
					
						
							|  |  |  |  | </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>euler432()</code> should return 754862080. | 
					
						
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										 |  |  |  |     testString: assert.strictEqual(euler432(), 754862080, '<code>euler432()</code> should return 754862080.'); | 
					
						
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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 euler432() { | 
					
						
							|  |  |  |  |   // Good luck! | 
					
						
							|  |  |  |  |   return true; | 
					
						
							|  |  |  |  | } | 
					
						
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							|  |  |  |  | euler432(); | 
					
						
							|  |  |  |  | ``` | 
					
						
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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> |