46 lines
749 B
Markdown
46 lines
749 B
Markdown
---
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id: 5900f3ab1000cf542c50febe
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title: 'Problem 63: Powerful digit counts'
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challengeType: 5
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forumTopicId: 302175
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---
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# --description--
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The 5-digit number, 16807 = 7<sup>5</sup>, is also a fifth power. Similarly, the 9-digit number, 134217728 = 8<sup>9</sup>, is a ninth power.
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How many `n`-digit positive integers exist which are also an `n`th power?
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# --hints--
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`powerfulDigitCounts()` should return a number.
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```js
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assert(typeof powerfulDigitCounts() === 'number');
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```
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`powerfulDigitCounts()` should return 49.
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```js
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assert.strictEqual(powerfulDigitCounts(), 49);
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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 powerfulDigitCounts() {
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return true;
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}
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powerfulDigitCounts();
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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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