45 lines
		
	
	
		
			642 B
		
	
	
	
		
			Markdown
		
	
	
	
	
	
			
		
		
	
	
			45 lines
		
	
	
		
			642 B
		
	
	
	
		
			Markdown
		
	
	
	
	
	
| ---
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| id: 5900f52c1000cf542c51003e
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| title: 'Problem 447: Retractions C'
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| challengeType: 5
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| forumTopicId: 302119
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| dashedName: problem-447-retractions-c
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| ---
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| 
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| # --description--
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| 
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| For every integer n>1, the family of functions fn,a,b is defined
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| 
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| by fn,a,b(x)≡ax+b mod n for a,b,x integer and 0
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| 
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| F(N)=∑R(n) for 2≤n≤N. F(107)≡638042271 (mod 1 000 000 007).
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| 
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| Find F(1014) (mod 1 000 000 007).
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| 
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| # --hints--
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| 
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| `euler447()` should return 530553372.
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| 
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| ```js
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| assert.strictEqual(euler447(), 530553372);
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| ```
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| 
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| # --seed--
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| 
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| ## --seed-contents--
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| 
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| ```js
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| function euler447() {
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| 
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|   return true;
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| }
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| 
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| euler447();
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| ```
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| 
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| # --solutions--
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| 
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| ```js
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| // solution required
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| ```
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