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								id: 5900f3ec1000cf542c50fefe
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								title: 'Problem 127: abc-hits'
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								challengeType: 5
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											2019-08-05 09:17:33 -07:00
										 
									 
								 
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								forumTopicId: 301754
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								dashedName: problem-127-abc-hits
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								---
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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 = 23 × 32 × 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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								GCD(a, b) = GCD(a, c) = GCD(b, c) = 1
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								a < b
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								a + b = c
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								rad(abc) < c
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								For example, (5, 27, 32) is an abc-hit, because:
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								GCD(5, 27) = GCD(5, 32) = GCD(27, 32) = 1
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								5 < 27
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								5 + 27 = 32
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								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 ∑c = 12523.
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								Find ∑c for c < 120000.
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								# --hints--
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								`euler127()` should return 18407904.
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								```js
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								assert.strictEqual(euler127(), 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 euler127() {
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								  return true;
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								}
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								euler127();
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								```
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								# --solutions--
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								```js
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								// solution required
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								```
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