66 lines
1.1 KiB
Markdown
66 lines
1.1 KiB
Markdown
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---
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id: 5
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localeTitle: 5900f53c1000cf542c51004e
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challengeType: 5
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title: 'Problem 463: A weird recurrence relation'
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---
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## Description
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<section id='description'>
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La función $ f $ se define para todos los enteros positivos de la siguiente manera:
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$ f (1) = 1 $
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$ f (3) = 3 $
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$ f (2n) = f (n) $
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$ f (4n) + 1) = 2f (2n + 1) - f (n) $
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$ f (4n + 3) = 3f (2n + 1) - 2f (n) $
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La función $ S (n) $ se define como $ \ sum_ {i = 1} ^ {n} f (i) $.
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$ S (8) = 22 $ y $ S (100) = 3604 $.
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Encuentra $ S (3 ^ {37}) $. Da los últimos 9 dígitos de tu respuesta.
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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>euler463()</code> debe devolver 808981553.
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testString: 'assert.strictEqual(euler463(), 808981553, "<code>euler463()</code> should return 808981553.");'
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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 euler463() {
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// Good luck!
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return true;
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}
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euler463();
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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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