47 lines
		
	
	
		
			742 B
		
	
	
	
		
			Markdown
		
	
	
	
	
	
		
		
			
		
	
	
			47 lines
		
	
	
		
			742 B
		
	
	
	
		
			Markdown
		
	
	
	
	
	
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								---
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								id: 5900f52c1000cf542c51003f
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								title: 'Problem 448: Average least common multiple'
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								challengeType: 5
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								forumTopicId: 302120
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								dashedName: problem-448-average-least-common-multiple
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								---
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								# --description--
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								The function lcm(a,b) denotes the least common multiple of a and b.
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								Let A(n) be the average of the values of lcm(n,i) for 1≤i≤n.
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								E.g: A(2)=(2+2)/2=2 and A(10)=(10+10+30+20+10+30+70+40+90+10)/10=32.
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								Let S(n)=∑A(k) for 1≤k≤n. S(100)=122726.
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								Find S(99999999019) mod 999999017.
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								# --hints--
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								`euler448()` should return 106467648.
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								```js
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								assert.strictEqual(euler448(), 106467648);
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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 euler448() {
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								  return true;
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								}
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								euler448();
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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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