62 lines
1.0 KiB
Markdown
62 lines
1.0 KiB
Markdown
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---
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id: 5
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localeTitle: 5900f4451000cf542c50ff57
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challengeType: 5
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title: 'Problem 216: Investigating the primality of numbers of the form 2n2-1'
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---
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## Description
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<section id='description'>
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Considere los números t (n) de la forma t (n) = 2n2-1 con n> 1.
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Los primeros números son 7, 17, 31, 49, 71, 97, 127 y 161.
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Resulta que solo 49 = 7 * 7 y 161 = 7 * 23 no son primos.
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Para n ≤ 10000 hay 2202 números t (n) que son primos.
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¿Cuántos números t (n) son primos para n ≤ 50,000,000?
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</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:
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- text: <code>euler216()</code> debe devolver 5437849.
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testString: 'assert.strictEqual(euler216(), 5437849, "<code>euler216()</code> should return 5437849.");'
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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
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function euler216() {
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// Good luck!
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return true;
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}
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euler216();
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```
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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
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// solution required
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```
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</section>
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