43 lines
821 B
Markdown
43 lines
821 B
Markdown
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---
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id: 5900f5331000cf542c510046
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title: 'Problem 455: Powers With Trailing Digits'
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challengeType: 5
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forumTopicId: 302129
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dashedName: problem-455-powers-with-trailing-digits
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---
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# --description--
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Let f(n) be the largest positive integer x less than 109 such that the last 9 digits of nx form the number x (including leading zeros), or zero if no such integer exists.
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For example:
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f(4) = 411728896 (4411728896 = ...490411728896) f(10) = 0 f(157) = 743757 (157743757 = ...567000743757) Σf(n), 2 ≤ n ≤ 103 = 442530011399 Find Σf(n), 2 ≤ n ≤ 106.
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# --hints--
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`euler455()` should return 450186511399999.
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```js
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assert.strictEqual(euler455(), 450186511399999);
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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 euler455() {
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return true;
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}
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euler455();
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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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