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							|  |  |  | id: 5900f5481000cf542c51005b | 
					
						
							|  |  |  | title: 'Problem 476: Circle Packing II' | 
					
						
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										 |  |  | challengeType: 5 | 
					
						
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										 |  |  | forumTopicId: 302153 | 
					
						
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										 |  |  | dashedName: problem-476-circle-packing-ii | 
					
						
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										 |  |  | # --description--
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										 |  |  | Let $R(a, b, c)$ be the maximum area covered by three non-overlapping circles inside a triangle with edge lengths $a$, $b$ and $c$. | 
					
						
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										 |  |  | Let $S(n)$ be the average value of $R(a, b, c)$ over all integer triplets $(a, b, c)$ such that $1 ≤ a ≤ b ≤ c < a + b ≤ n$. | 
					
						
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										 |  |  | You are given $S(2) = R(1, 1, 1) ≈ 0.31998$, $S(5) ≈ 1.25899$. | 
					
						
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										 |  |  | Find $S(1803)$ rounded to 5 decimal places behind the decimal point. | 
					
						
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										 |  |  | # --hints--
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										 |  |  | `circlePackingTwo()` should return `110242.87794`. | 
					
						
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										 |  |  | ```js | 
					
						
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										 |  |  | assert.strictEqual(circlePackingTwo(), 110242.87794); | 
					
						
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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 circlePackingTwo() { | 
					
						
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										 |  |  |   return true; | 
					
						
							|  |  |  | } | 
					
						
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										 |  |  | circlePackingTwo(); | 
					
						
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										 |  |  | ``` | 
					
						
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										 |  |  | # --solutions--
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							|  |  |  | ```js | 
					
						
							|  |  |  | // solution required | 
					
						
							|  |  |  | ``` |