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							|  |  |  |  | id: 5900f4d61000cf542c50ffe9 | 
					
						
							|  |  |  |  | title: 'Problem 362: Squarefree factors' | 
					
						
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										 |  |  |  | challengeType: 5 | 
					
						
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										 |  |  |  | forumTopicId: 302023 | 
					
						
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										 |  |  |  | dashedName: problem-362-squarefree-factors | 
					
						
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										 |  |  |  | # --description--
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										 |  |  |  | Consider the number 54. | 
					
						
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										 |  |  |  | 54 can be factored in 7 distinct ways into one or more factors larger than 1: | 
					
						
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										 |  |  |  | 54, 2×27, 3×18, 6×9, 3×3×6, 2×3×9 and 2×3×3×3. | 
					
						
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										 |  |  |  | If we require that the factors are all squarefree only two ways remain: 3×3×6 and 2×3×3×3. | 
					
						
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										 |  |  |  | Let's call Fsf(n) the number of ways n can be factored into one or more squarefree factors larger than 1, so Fsf(54)=2. | 
					
						
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							|  |  |  |  | Let S(n) be ∑Fsf(k) for k=2 to n. | 
					
						
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							|  |  |  |  | S(100)=193. | 
					
						
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							|  |  |  |  | Find S(10 000 000 000). | 
					
						
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										 |  |  |  | # --hints--
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										 |  |  |  | `euler362()` should return 457895958010. | 
					
						
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										 |  |  |  | ```js | 
					
						
							|  |  |  |  | assert.strictEqual(euler362(), 457895958010); | 
					
						
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										 |  |  |  | ``` | 
					
						
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										 |  |  |  | # --seed--
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										 |  |  |  | ## --seed-contents--
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							|  |  |  |  | ```js | 
					
						
							|  |  |  |  | function euler362() { | 
					
						
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										 |  |  |  |   return true; | 
					
						
							|  |  |  |  | } | 
					
						
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							|  |  |  |  | euler362(); | 
					
						
							|  |  |  |  | ``` | 
					
						
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										 |  |  |  | # --solutions--
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							|  |  |  |  | ```js | 
					
						
							|  |  |  |  | // solution required | 
					
						
							|  |  |  |  | ``` |