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										 |  |  | --- | 
					
						
							|  |  |  | id: 5900f4b01000cf542c50ffc2 | 
					
						
							|  |  |  | challengeType: 5 | 
					
						
							|  |  |  | title: 'Problem 323: Bitwise-OR operations on random integers' | 
					
						
							|  |  |  | --- | 
					
						
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							|  |  |  | ## Description
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							|  |  |  | <section id='description'> | 
					
						
							|  |  |  | Let y0, y1, y2,... be a sequence of random unsigned 32 bit integers | 
					
						
							|  |  |  | (i.e. 0 ≤ yi < 232, every value equally likely). | 
					
						
							|  |  |  | For the sequence xi the following recursion is given:x0 = 0 and | 
					
						
							|  |  |  | xi = xi-1| yi-1, for i > 0. ( | is the bitwise-OR operator) | 
					
						
							|  |  |  | It can be seen that eventually there will be an index N such that xi = 232 -1 (a bit-pattern of all ones) for all i ≥ N. | 
					
						
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										 |  |  | Find the expected value of N. | 
					
						
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										 |  |  | Give your answer rounded to 10 digits after the decimal point. | 
					
						
							|  |  |  | </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>euler323()</code> should return 6.3551758451. | 
					
						
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										 |  |  |     testString: assert.strictEqual(euler323(), 6.3551758451, '<code>euler323()</code> should return 6.3551758451.'); | 
					
						
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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 euler323() { | 
					
						
							|  |  |  |   // Good luck! | 
					
						
							|  |  |  |   return true; | 
					
						
							|  |  |  | } | 
					
						
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							|  |  |  | euler323(); | 
					
						
							|  |  |  | ``` | 
					
						
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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> |