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								---
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								id: 5900f48d1000cf542c50ff9f
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								title: 'Problem 288: An enormous factorial'
							 
						 
					
						
							
								
									
										
										
										
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								challengeType: 5
							 
						 
					
						
							
								
									
										
										
										
											2019-08-05 09:17:33 -07:00 
										
									 
								 
							 
							
								
									
										 
								
							 
							
								 
							
							
								forumTopicId: 301939
							 
						 
					
						
							
								
									
										
										
										
											2021-01-13 03:31:00 +01:00 
										
									 
								 
							 
							
								
									
										 
								
							 
							
								 
							
							
								dashedName: problem-288-an-enormous-factorial
							 
						 
					
						
							
								
									
										
										
										
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								---
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
									
										
										
										
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								# --description--
  
						 
					
						
							
								
									
										
										
										
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								For any prime $p$ the number $N(p,q)$ is defined by $N(p,q) = \sum_{n=0}^q T_n \times p^n$ with $T_n$ generated by the following random number generator:
							 
						 
					
						
							
								
									
										
										
										
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								$$\begin{align}
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								  &  S_0 = 290797 \\\\
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								  &  S_{n + 1} = {S_n}^2\bmod 50\\,515\\,093 \\\\
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								  &  T_n = S_n\bmod p
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								\end{align}$$
							 
						 
					
						
							
								
									
										
										
										
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								Let $Nfac(p,q)$ be the factorial of $N(p,q)$.
							 
						 
					
						
							
								
									
										
										
										
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								Let $NF(p,q)$ be the number of factors $p$ in $Nfac(p,q)$.
							 
						 
					
						
							
								
									
										
										
										
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								You are given that $NF(3,10000) \bmod 3^{20} = 624\\,955\\,285$.
							 
						 
					
						
							
								
									
										
										
										
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								Find $NF(61,{10}^7)\bmod {61}^{10}$.
							 
						 
					
						
							
								
									
										
										
										
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								# --hints--
  
						 
					
						
							
								
									
										
										
										
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								`enormousFactorial()`  should return `605857431263982000` . 
						 
					
						
							
								
									
										
										
										
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								```js
							 
						 
					
						
							
								
									
										
										
										
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								assert.strictEqual(enormousFactorial(), 605857431263982000);
							 
						 
					
						
							
								
									
										
										
										
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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 enormousFactorial() {
							 
						 
					
						
							
								
									
										
										
										
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								  return true;
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								}
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
									
										
										
										
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								enormousFactorial();
							 
						 
					
						
							
								
									
										
										
										
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								```
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
									
										
										
										
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								# --solutions--
  
						 
					
						
							
								
									
										
										
										
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								```js
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								// solution required
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								```