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								id: 5900f4311000cf542c50ff43
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								title: 'Problem 195: Inscribed circles of triangles with one angle of 60 degrees'
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								challengeType: 5
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											2019-08-05 09:17:33 -07:00
										 
									 
								 
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								forumTopicId: 301833
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											2021-01-13 03:31:00 +01:00
										 
									 
								 
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								dashedName: problem-195-inscribed-circles-of-triangles-with-one-angle-of-60-degrees
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								---
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								# --description--
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								Let's call an integer sided triangle with exactly one angle of 60 degrees a 60-degree triangle.
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								Let r be the radius of the inscribed circle of such a 60-degree triangle.
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								There are 1234 60-degree triangles for which r ≤ 100.
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								Let T(n) be the number of 60-degree triangles for which r ≤ n, so
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								T(100) = 1234, T(1000) = 22767, and T(10000) = 359912.
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								Find T(1053779).
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								# --hints--
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								`euler195()` should return 75085391.
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								```js
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								assert.strictEqual(euler195(), 75085391);
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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 euler195() {
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								  return true;
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								}
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								euler195();
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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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