46 lines
788 B
Markdown
46 lines
788 B
Markdown
---
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id: 5900f4c31000cf542c50ffd5
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title: 'Problem 342: The totient of a square is a cube'
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challengeType: 5
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forumTopicId: 302001
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dashedName: problem-342-the-totient-of-a-square-is-a-cube
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---
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# --description--
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Consider the number 50.
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${50}^2 = 2500 = 2^2 × 5^4$, so $φ(2500) = 2 × 4 × 5^3 = 8 × 5^3 = 2^3 × 5^3$. $φ$ denotes Euler's totient function.
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So 2500 is a square and $φ(2500)$ is a cube.
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Find the sum of all numbers $n$, $1 < n < {10}^{10}$ such that $φ(n^2)$ is a cube.
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# --hints--
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`totientOfSquare()` should return `5943040885644`.
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```js
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assert.strictEqual(totientOfSquare(), 5943040885644);
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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 totientOfSquare() {
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return true;
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}
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totientOfSquare();
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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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