45 lines
786 B
Markdown
45 lines
786 B
Markdown
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---
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id: 5900f5271000cf542c510039
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title: 'Problem 442: Eleven-free integers'
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challengeType: 5
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forumTopicId: 302114
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dashedName: problem-442-eleven-free-integers
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---
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# --description--
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An integer is called eleven-free if its decimal expansion does not contain any substring representing a power of 11 except 1.
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For example, 2404 and 13431 are eleven-free, while 911 and 4121331 are not.
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Let E(n) be the nth positive eleven-free integer. For example, E(3) = 3, E(200) = 213 and E(500 000) = 531563.
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Find E(1018).
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# --hints--
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`euler442()` should return 1295552661530920200.
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```js
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assert.strictEqual(euler442(), 1295552661530920200);
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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 euler442() {
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return true;
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}
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euler442();
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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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