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							|  |  |  | id: 5900f4791000cf542c50ff8c | 
					
						
							|  |  |  | title: 'Problem 269: Polynomials with at least one integer root' | 
					
						
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										 |  |  | challengeType: 5 | 
					
						
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										 |  |  | forumTopicId: 301918 | 
					
						
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											2021-01-13 03:31:00 +01:00
										 |  |  | dashedName: problem-269-polynomials-with-at-least-one-integer-root | 
					
						
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										 |  |  | # --description--
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										 |  |  | A root or zero of a polynomial $P(x)$ is a solution to the equation $P(x) = 0$. | 
					
						
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										 |  |  | Define $P_n$ as the polynomial whose coefficients are the digits of $n$. | 
					
						
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										 |  |  | For example, $P_{5703}(x) = 5x^3 + 7x^2 + 3$. | 
					
						
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										 |  |  | We can see that: | 
					
						
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										 |  |  | - $P_n(0)$ is the last digit of $n$, | 
					
						
							|  |  |  | - $P_n(1)$ is the sum of the digits of $n$, | 
					
						
							|  |  |  | - $Pn(10)$ is $n$ itself. | 
					
						
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										 |  |  | Define $Z(k)$ as the number of positive integers, $n$, not exceeding $k$ for which the polynomial $P_n$ has at least one integer root. | 
					
						
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							|  |  |  | It can be verified that $Z(100\\,000)$ is 14696. | 
					
						
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							|  |  |  | What is $Z({10}^{16})$? | 
					
						
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										 |  |  | # --hints--
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										 |  |  | `polynomialsWithOneIntegerRoot()` should return `1311109198529286`. | 
					
						
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										 |  |  | ```js | 
					
						
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										 |  |  | assert.strictEqual(polynomialsWithOneIntegerRoot(), 1311109198529286); | 
					
						
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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 polynomialsWithOneIntegerRoot() { | 
					
						
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										 |  |  |   return true; | 
					
						
							|  |  |  | } | 
					
						
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										 |  |  | polynomialsWithOneIntegerRoot(); | 
					
						
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										 |  |  | ``` | 
					
						
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										 |  |  | # --solutions--
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							|  |  |  | ```js | 
					
						
							|  |  |  | // solution required | 
					
						
							|  |  |  | ``` |