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								---
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								id: 5900f43c1000cf542c50ff4e
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								title: 'Problem 207: Integer partition equations'
							 
						 
					
						
							
								
									
										
										
										
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								challengeType: 5
							 
						 
					
						
							
								
									
										
										
										
											2019-08-05 09:17:33 -07:00 
										
									 
								 
							 
							
								
									
										 
								
							 
							
								 
							
							
								forumTopicId: 301848
							 
						 
					
						
							
								
									
										
										
										
											2021-01-13 03:31:00 +01:00 
										
									 
								 
							 
							
								
									
										 
								
							 
							
								 
							
							
								dashedName: problem-207-integer-partition-equations
							 
						 
					
						
							
								
									
										
										
										
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								---
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
									
										
										
										
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								# --description--
  
						 
					
						
							
								
									
										
										
										
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								For some positive integers $k$, there exists an integer partition of the form $4^t = 2^t + k$,
							 
						 
					
						
							
								
									
										
										
										
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								where $4^t$, $2^t$, and $k$ are all positive integers and $t$ is a real number.
							 
						 
					
						
							
								
									
										
										
										
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								The first two such partitions are $4^1 = 2^1 + 2$ and $4^{1.584\\,962\\,5\ldots} = 2^{1.584\\,962\\,5\ldots} + 6$.
							 
						 
					
						
							
								
									
										
										
										
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								Partitions where $t$ is also an integer are called perfect. For any $m ≥ 1$ let $P(m)$ be the proportion of such partitions that are perfect with $k ≤ m$.
							 
						 
					
						
							
								
									
										
										
										
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								Thus $P(6) = \frac{1}{2}$.
							 
						 
					
						
							
								
									
										
										
										
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								In the following table are listed some values of $P(m)$
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								$$\begin{align}
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								  &  P(5) = \frac{1}{1}    \\\\
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								  &  P(10) = \frac{1}{2}   \\\\
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								  &  P(15) = \frac{2}{3}   \\\\
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								  &  P(20) = \frac{1}{2}   \\\\
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								  &  P(25) = \frac{1}{2}   \\\\
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								  &  P(30) = \frac{2}{5}   \\\\
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								  &  \ldots                \\\\
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								  &  P(180) = \frac{1}{4}  \\\\
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								  &  P(185) = \frac{3}{13}
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								\end{align}$$
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								Find the smallest $m$ for which $P(m) <  \frac{1}{12\\,345}$
							 
						 
					
						
							
								
									
										
										
										
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								# --hints--
  
						 
					
						
							
								
									
										
										
										
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								`integerPartitionEquations()`  should return `44043947822` . 
						 
					
						
							
								
									
										
										
										
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								```js
							 
						 
					
						
							
								
									
										
										
										
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								assert.strictEqual(integerPartitionEquations(), 44043947822);
							 
						 
					
						
							
								
									
										
										
										
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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 integerPartitionEquations() {
							 
						 
					
						
							
								
									
										
										
										
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								  return true;
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								}
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
									
										
										
										
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								integerPartitionEquations();
							 
						 
					
						
							
								
									
										
										
										
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								```
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
									
										
										
										
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								# --solutions--
  
						 
					
						
							
								
									
										
										
										
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								```js
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								// solution required
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								```