45 lines
919 B
Markdown
45 lines
919 B
Markdown
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---
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id: 5900f4de1000cf542c50fff1
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title: 'Problem 370: Geometric triangles'
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challengeType: 5
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forumTopicId: 302032
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dashedName: problem-370-geometric-triangles
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---
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# --description--
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Let us define a geometric triangle as an integer sided triangle with sides $a ≤ b ≤ c$ so that its sides form a geometric progression, i.e. $b^2 = a \times c$.
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An example of such a geometric triangle is the triangle with sides $a = 144$, $b = 156$ and $c = 169$.
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There are $861\\,805$ geometric triangles with $\text{perimeter} ≤ {10}^6$.
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How many geometric triangles exist with $\text{perimeter} ≤ 2.5 \times {10}^{13}$?
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# --hints--
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`geometricTriangles()` should return `41791929448408`.
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```js
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assert.strictEqual(geometricTriangles(), 41791929448408);
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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 geometricTriangles() {
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return true;
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}
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geometricTriangles();
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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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