43 lines
		
	
	
		
			613 B
		
	
	
	
		
			Markdown
		
	
	
	
	
	
		
		
			
		
	
	
			43 lines
		
	
	
		
			613 B
		
	
	
	
		
			Markdown
		
	
	
	
	
	
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								---
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								id: 5900f51e1000cf542c510030
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								title: 'Problem 432: Totient sum'
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								challengeType: 5
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								forumTopicId: 302103
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								dashedName: problem-432-totient-sum
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								---
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								# --description--
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								Let S(n,m) = ∑φ(n × i) for 1 ≤ i ≤ m. (φ is Euler's totient function)
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								You are given that S(510510,106 )= 45480596821125120.
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								Find S(510510,1011). Give the last 9 digits of your answer.
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								# --hints--
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								`euler432()` should return 754862080.
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								```js
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								assert.strictEqual(euler432(), 754862080);
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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 euler432() {
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								  return true;
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								}
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								euler432();
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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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