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											2018-09-30 23:01:58 +01:00
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							|  |  |  | id: 5900f4b91000cf542c50ffcb | 
					
						
							|  |  |  | challengeType: 5 | 
					
						
							|  |  |  | title: 'Problem 332: Spherical triangles' | 
					
						
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							|  |  |  | ## Description
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							|  |  |  | <section id='description'> | 
					
						
							|  |  |  | A spherical triangle is a figure formed on the surface of a sphere by three great circular arcs intersecting pairwise in three vertices. | 
					
						
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							|  |  |  | Let C(r) be the sphere with the centre (0,0,0) and radius r. | 
					
						
							|  |  |  | Let Z(r) be the set of points on the surface of C(r) with integer coordinates. | 
					
						
							|  |  |  | Let T(r) be the set of spherical triangles with vertices in Z(r). | 
					
						
							|  |  |  | Degenerate spherical triangles, formed by three points on the same great arc, are not included in T(r). | 
					
						
							|  |  |  | Let A(r) be the area of the smallest spherical triangle in T(r). | 
					
						
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							|  |  |  | For example A(14) is 3.294040 rounded to six decimal places. | 
					
						
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							|  |  |  | Find  A(r). Give your answer rounded to six decimal places. | 
					
						
							|  |  |  | </section> | 
					
						
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							|  |  |  | ## Instructions
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							|  |  |  | <section id='instructions'> | 
					
						
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							|  |  |  | </section> | 
					
						
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							|  |  |  | ## Tests
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							|  |  |  | <section id='tests'> | 
					
						
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							|  |  |  | ```yml | 
					
						
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										 |  |  | tests: | 
					
						
							|  |  |  |   - text: <code>euler332()</code> should return 2717.751525. | 
					
						
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										 |  |  |     testString: assert.strictEqual(euler332(), 2717.751525, '<code>euler332()</code> should return 2717.751525.'); | 
					
						
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							|  |  |  | ``` | 
					
						
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							|  |  |  | </section> | 
					
						
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							|  |  |  | ## Challenge Seed
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							|  |  |  | <section id='challengeSeed'> | 
					
						
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							|  |  |  | <div id='js-seed'> | 
					
						
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							|  |  |  | ```js | 
					
						
							|  |  |  | function euler332() { | 
					
						
							|  |  |  |   // Good luck! | 
					
						
							|  |  |  |   return true; | 
					
						
							|  |  |  | } | 
					
						
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							|  |  |  | euler332(); | 
					
						
							|  |  |  | ``` | 
					
						
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							|  |  |  | </div> | 
					
						
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							|  |  |  | </section> | 
					
						
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							|  |  |  | ## Solution
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							|  |  |  | <section id='solution'> | 
					
						
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							|  |  |  | ```js | 
					
						
							|  |  |  | // solution required | 
					
						
							|  |  |  | ``` | 
					
						
							|  |  |  | </section> |