c18554dd44
* fix: clean-up Project Euler 341-360 * fix: improve wording Co-authored-by: Sem Bauke <46919888+Sembauke@users.noreply.github.com> * fix: corrections from review Co-authored-by: Tom <20648924+moT01@users.noreply.github.com> Co-authored-by: Sem Bauke <46919888+Sembauke@users.noreply.github.com> Co-authored-by: Tom <20648924+moT01@users.noreply.github.com>
49 lines
1.3 KiB
Markdown
49 lines
1.3 KiB
Markdown
---
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id: 5900f4cb1000cf542c50ffde
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title: 'Problem 351: Hexagonal orchards'
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challengeType: 5
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forumTopicId: 302011
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dashedName: problem-351-hexagonal-orchards
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---
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# --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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<img class="img-responsive center-block" alt="hexagonal orchard of order 5, with highlighted in green points, which are hidden from the center by a point closer to it" src="https://cdn.freecodecamp.org/curriculum/project-euler/hexagonal-orchards.png" style="background-color: white; padding: 10px;">
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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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$H(5) = 30$. $H(10) = 138$. $H(1\\,000)$ = $1\\,177\\,848$.
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Find $H(100\\,000\\,000)$.
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# --hints--
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`hexagonalOrchards()` should return `11762187201804552`.
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```js
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assert.strictEqual(hexagonalOrchards(), 11762187201804552);
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```
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# --seed--
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## --seed-contents--
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```js
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function hexagonalOrchards() {
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return true;
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}
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hexagonalOrchards();
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```
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# --solutions--
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```js
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// solution required
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```
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