49 lines
883 B
Markdown
49 lines
883 B
Markdown
---
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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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forumTopicId: 301833
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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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