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---
id: 5900f4491000cf542c50ff5c
title: 'Problem 221: Alexandrian Integers'
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challengeType: 5
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forumTopicId: 301864
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---
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# --description--
We shall call a positive integer A an "Alexandrian integer", if there exist integers p, q, r such that: A = p · q · r and 1/A = 1/p + 1/q + 1/r
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<!-- TODO Use MathJax -->
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For example, 630 is an Alexandrian integer (p = 5, q = − 7, r = − 18). In fact, 630 is the 6th Alexandrian integer, the first 6 Alexandrian integers being: 6, 42, 120, 156, 420 and 630.
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Find the 150000th Alexandrian integer.
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# --hints--
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`euler221()` should return 1884161251122450.
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```js
assert.strictEqual(euler221(), 1884161251122450);
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```
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# --seed--
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## --seed-contents--
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```js
function euler221() {
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return true;
}
euler221();
```
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# --solutions--
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```js
// solution required
```