22afc2a0ca
Co-authored-by: Oliver Eyton-Williams <ojeytonwilliams@gmail.com> Co-authored-by: Kristofer Koishigawa <scissorsneedfoodtoo@gmail.com> Co-authored-by: Beau Carnes <beaucarnes@gmail.com>
71 lines
1.1 KiB
Markdown
71 lines
1.1 KiB
Markdown
---
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id: 5900f5111000cf542c510023
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challengeType: 5
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isHidden: false
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title: 'Problem 420: 2x2 positive integer matrix'
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forumTopicId: 302090
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---
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## Description
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<section id='description'>
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A positive integer matrix is a matrix whose elements are all positive integers.
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Some positive integer matrices can be expressed as a square of a positive integer matrix in two different ways. Here is an example:
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We define F(N) as the number of the 2x2 positive integer matrices which have a trace less than N and which can be expressed as a square of a positive integer matrix in two different ways.
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We can verify that F(50) = 7 and F(1000) = 1019.
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Find F(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>euler420()</code> should return 145159332.
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testString: assert.strictEqual(euler420(), 145159332);
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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 euler420() {
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// Good luck!
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return true;
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}
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euler420();
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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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