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							|  |  |  |  | id: 5900f3ec1000cf542c50fefe | 
					
						
							|  |  |  |  | title: 'Problem 127: abc-hits' | 
					
						
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										 |  |  |  | challengeType: 5 | 
					
						
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										 |  |  |  | forumTopicId: 301754 | 
					
						
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										 |  |  |  | dashedName: problem-127-abc-hits | 
					
						
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										 |  |  |  | # --description--
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										 |  |  |  | The radical of $n$, $rad(n)$, is the product of distinct prime factors of $n$. For example, $504 = 2^3 × 3^2 × 7$, so $rad(504) = 2 × 3 × 7 = 42$. | 
					
						
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										 |  |  |  | We shall define the triplet of positive integers (a, b, c) to be an abc-hit if: | 
					
						
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										 |  |  |  | 1. $GCD(a, b) = GCD(a, c) = GCD(b, c) = 1$ | 
					
						
							|  |  |  |  | 2. $a < b$ | 
					
						
							|  |  |  |  | 3. $a + b = c$ | 
					
						
							|  |  |  |  | 4. $rad(abc) < c$ | 
					
						
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										 |  |  |  | For example, (5, 27, 32) is an abc-hit, because: | 
					
						
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										 |  |  |  | 1. $GCD(5, 27) = GCD(5, 32) = GCD(27, 32) = 1$ | 
					
						
							|  |  |  |  | 2. $5 < 27$ | 
					
						
							|  |  |  |  | 3. $5 + 27 = 32$ | 
					
						
							|  |  |  |  | 4. $rad(4320) = 30 < 32$ | 
					
						
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										 |  |  |  | It turns out that abc-hits are quite rare and there are only thirty-one abc-hits for $c < 1000$, with $\sum{c} = 12523$. | 
					
						
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										 |  |  |  | Find $\sum{c}$ for $c < 120000$. | 
					
						
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										 |  |  |  | # --hints--
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										 |  |  |  | `abcHits()` should return `18407904`. | 
					
						
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										 |  |  |  | ```js | 
					
						
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										 |  |  |  | assert.strictEqual(abcHits(), 18407904); | 
					
						
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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 abcHits() { | 
					
						
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										 |  |  |  |   return true; | 
					
						
							|  |  |  |  | } | 
					
						
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										 |  |  |  | abcHits(); | 
					
						
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										 |  |  |  | ``` | 
					
						
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										 |  |  |  | # --solutions--
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							|  |  |  |  | ```js | 
					
						
							|  |  |  |  | // solution required | 
					
						
							|  |  |  |  | ``` |