72 lines
1.2 KiB
Markdown
72 lines
1.2 KiB
Markdown
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---
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id: 5
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localeTitle: 5900f4ab1000cf542c50ffbe
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challengeType: 5
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title: 'Problem 319: Bounded Sequences'
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---
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## Description
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<section id='description'>
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Sean x1, x2, ..., xn una secuencia de longitud n tal que:
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x1 = 2
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para todos 1 <i ≤ n: xi-1 <xi
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para todos i y j con 1 ≤ i, j ≤ n: (xi) j <(xj + 1) i
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Solo hay cinco secuencias de este tipo de longitud 2, a saber:
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{2,4}, {2,5}, {2,6}, {2, 7} y {2,8}.
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Hay 293 tales secuencias de longitud 5; A continuación se dan tres ejemplos:
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{2,5,11,25,55}, {2,6,14,36,88}, {2,8,22,64,181}.
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Sea t (n) el número de tales secuencias de longitud n.
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Te dan que t (10) = 86195 yt (20) = 5227991891.
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Encuentra t (1010) y da tu respuesta módulo 109.
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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>euler319()</code> debe devolver 268457129.
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testString: 'assert.strictEqual(euler319(), 268457129, "<code>euler319()</code> should return 268457129.");'
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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 euler319() {
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// Good luck!
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return true;
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}
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euler319();
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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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