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											2018-09-30 23:01:58 +01:00
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							|  |  |  | id: 5900f4ae1000cf542c50ffbf | 
					
						
							|  |  |  | challengeType: 5 | 
					
						
							|  |  |  | title: 'Problem 320: Factorials divisible by a huge integer' | 
					
						
							|  |  |  | --- | 
					
						
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							|  |  |  | ## Description
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							|  |  |  | <section id='description'> | 
					
						
							|  |  |  | Let N(i) be the smallest integer n such that n! is divisible by (i!)1234567890 | 
					
						
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							|  |  |  | Let S(u)=∑N(i) for 10 ≤ i ≤ u. | 
					
						
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							|  |  |  | S(1000)=614538266565663. | 
					
						
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							|  |  |  | Find S(1 000 000) mod 1018. | 
					
						
							|  |  |  | </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>euler320()</code> should return 278157919195482660. | 
					
						
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										 |  |  |     testString: assert.strictEqual(euler320(), 278157919195482660, '<code>euler320()</code> should return 278157919195482660.'); | 
					
						
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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 euler320() { | 
					
						
							|  |  |  |   // Good luck! | 
					
						
							|  |  |  |   return true; | 
					
						
							|  |  |  | } | 
					
						
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							|  |  |  | euler320(); | 
					
						
							|  |  |  | ``` | 
					
						
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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> |