63 lines
1.4 KiB
Markdown
63 lines
1.4 KiB
Markdown
---
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id: 5900f4571000cf542c50ff69
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challengeType: 5
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title: 'Problem 234: Semidivisible numbers'
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---
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## Description
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<section id='description'>
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For an integer n ≥ 4, we define the lower prime square root of n, denoted by lps(n), as the largest prime ≤ √n and the upper prime square root of n, ups(n), as the smallest prime ≥ √n.
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So, for example, lps(4) = 2 = ups(4), lps(1000) = 31, ups(1000) = 37.
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Let us call an integer n ≥ 4 semidivisible, if one of lps(n) and ups(n) divides n, but not both.
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The sum of the semidivisible numbers not exceeding 15 is 30, the numbers are 8, 10 and 12. 15 is not semidivisible because it is a multiple of both lps(15) = 3 and ups(15) = 5.
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As a further example, the sum of the 92 semidivisible numbers up to 1000 is 34825.
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What is the sum of all semidivisible numbers not exceeding 999966663333 ?
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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>euler234()</code> should return 1259187438574927000.
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testString: 'assert.strictEqual(euler234(), 1259187438574927000, "<code>euler234()</code> should return 1259187438574927000.");'
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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 euler234() {
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// Good luck!
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return true;
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}
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euler234();
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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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