77 lines
1.2 KiB
Markdown
77 lines
1.2 KiB
Markdown
---
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id: 5900f4cb1000cf542c50ffde
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challengeType: 5
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title: 'Problem 351: Hexagonal orchards'
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forumTopicId: 302011
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---
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## Description
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<section id='description'>
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A hexagonal orchard of order n is a triangular lattice made up of points within a regular hexagon with side n. The following is an example of a hexagonal orchard of order 5:
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Highlighted in green are the points which are hidden from the center by a point closer to it. It can be seen that for a hexagonal orchard of order 5, 30 points are hidden from the center.
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Let H(n) be the number of points hidden from the center in a hexagonal orchard of order n.
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H(5) = 30. H(10) = 138. H(1 000) = 1177848.
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Find H(100 000 000).
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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>euler351()</code> should return 11762187201804552.
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testString: assert.strictEqual(euler351(), 11762187201804552);
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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 euler351() {
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return true;
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}
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euler351();
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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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