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							|  |  |  | id: 5900f4861000cf542c50ff99 | 
					
						
							|  |  |  | title: 'Problem 282: The Ackermann function' | 
					
						
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										 |  |  | challengeType: 5 | 
					
						
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										 |  |  | forumTopicId: 301933 | 
					
						
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										 |  |  | dashedName: problem-282-the-ackermann-function | 
					
						
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										 |  |  | --- | 
					
						
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										 |  |  | # --description--
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										 |  |  | For non-negative integers $m$, $n$, the Ackermann function $A(m, n)$ is defined as follows: | 
					
						
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										 |  |  | $$A(m, n) = | 
					
						
							|  |  |  | \begin{cases} | 
					
						
							|  |  |  | n + 1                 & \text{if $m = 0$}             \\\\ | 
					
						
							|  |  |  | A(m - 1, 1)           & \text{if $m > 0$ and $n = 0$} \\\\ | 
					
						
							|  |  |  | A(m - 1, A(m, n - 1)) & \text{if $m > 0$ and $n > 0$} | 
					
						
							|  |  |  | \end{cases}$$ | 
					
						
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										 |  |  | For example $A(1, 0) = 2$, $A(2, 2) = 7$ and $A(3, 4) = 125$. | 
					
						
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							|  |  |  | Find $\displaystyle\sum_{n = 0}^6 A(n, n)$ and give your answer mod ${14}^8$. | 
					
						
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										 |  |  | # --hints--
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										 |  |  | `ackermanFunction()` should return `1098988351`. | 
					
						
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										 |  |  | ```js | 
					
						
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										 |  |  | assert.strictEqual(ackermanFunction(), 1098988351); | 
					
						
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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 ackermanFunction() { | 
					
						
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										 |  |  |   return true; | 
					
						
							|  |  |  | } | 
					
						
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										 |  |  | ackermanFunction(); | 
					
						
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										 |  |  | ``` | 
					
						
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										 |  |  | # --solutions--
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							|  |  |  | ```js | 
					
						
							|  |  |  | // solution required | 
					
						
							|  |  |  | ``` |