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								---
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								id: 5900f4931000cf542c50ffa4
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								title: 'Problem 293: Pseudo-Fortunate Numbers'
							 
						 
					
						
							
								
									
										
										
										
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								challengeType: 5
							 
						 
					
						
							
								
									
										
										
										
											2019-08-05 09:17:33 -07:00 
										
									 
								 
							 
							
								
									
										 
								
							 
							
								 
							
							
								forumTopicId: 301945
							 
						 
					
						
							
								
									
										
										
										
											2021-01-13 03:31:00 +01:00 
										
									 
								 
							 
							
								
									
										 
								
							 
							
								 
							
							
								dashedName: problem-293-pseudo-fortunate-numbers
							 
						 
					
						
							
								
									
										
										
										
											2018-09-30 23:01:58 +01:00 
										
									 
								 
							 
							
								
							 
							
								 
							
							
								---
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
									
										
										
										
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								# --description--
  
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
									
										
										
										
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								An even positive integer $N$ will be called admissible, if it is a power of 2 or its distinct prime factors are consecutive primes.
							 
						 
					
						
							
								
									
										
										
										
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								The first twelve admissible numbers are 2, 4, 6, 8, 12, 16, 18, 24, 30, 32, 36, 48.
							 
						 
					
						
							
								
									
										
										
										
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								If $N$ is admissible, the smallest integer $M > 1$ such that $N + M$ is prime, will be called the pseudo-Fortunate number for $N$.
							 
						 
					
						
							
								
									
										
										
										
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								For example, $N = 630$ is admissible since it is even and its distinct prime factors are the consecutive primes 2, 3, 5 and 7. The next prime number after 631 is 641; hence, the pseudo-Fortunate number for 630 is $M = 11$. It can also be seen that the pseudo-Fortunate number for 16 is 3.
							 
						 
					
						
							
								
									
										
										
										
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								Find the sum of all distinct pseudo-Fortunate numbers for admissible numbers $N$ less than ${10}^9$.
							 
						 
					
						
							
								
									
										
										
										
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								# --hints--
  
						 
					
						
							
								
									
										
										
										
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								`pseudoFortunateNumbers()`  should return `2209` . 
						 
					
						
							
								
									
										
										
										
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								```js
							 
						 
					
						
							
								
									
										
										
										
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								assert.strictEqual(pseudoFortunateNumbers(), 2209);
							 
						 
					
						
							
								
									
										
										
										
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								```
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
									
										
										
										
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								# --seed--
  
						 
					
						
							
								
									
										
										
										
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								## --seed-contents--
  
						 
					
						
							
								
									
										
										
										
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								```js
							 
						 
					
						
							
								
									
										
										
										
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								function pseudoFortunateNumbers() {
							 
						 
					
						
							
								
									
										
										
										
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								  return true;
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								}
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
									
										
										
										
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								pseudoFortunateNumbers();
							 
						 
					
						
							
								
									
										
										
										
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								```
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
									
										
										
										
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								# --solutions--
  
						 
					
						
							
								
									
										
										
										
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								```js
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								// solution required
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								```