72 lines
1.3 KiB
Markdown
72 lines
1.3 KiB
Markdown
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---
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id: 5
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localeTitle: 5900f5311000cf542c510042
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challengeType: 5
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title: 'Problem 451: Modular inverses'
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---
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## Description
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<section id='description'>
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Considere el número 15.
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Hay ocho números positivos menores que 15 que son coprime a 15: 1, 2, 4, 7, 8, 11, 13, 14.
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Los inversos modulares de estos números módulo 15 son: 1, 8, 4, 13, 2, 11, 7, 14
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porque
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1 * 1 mod 15 = 1
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2 * 8 = 16 mod 15 = 1
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4 * 4 = 16 mod 15 = 1
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7 * 13 = 91 mod 15 = 1
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11 * 11 = 121 mod 15 = 1
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14 * 14 = 196 mod 15 = 1
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Sea I (n) el mayor número positivo m más pequeño que n-1, de modo que el inverso modular de m módulo n es igual a m en sí.
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Entonces yo (15) = 11.
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También I (100) = 51 y I (7) = 1.
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Encuentra ∑I (n) para 3≤n≤2 · 107
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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>euler451()</code> debe devolver 153651073760956.
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testString: 'assert.strictEqual(euler451(), 153651073760956, "<code>euler451()</code> should return 153651073760956.");'
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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 euler451() {
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// Good luck!
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return true;
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}
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euler451();
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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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