69 lines
1.0 KiB
Markdown
69 lines
1.0 KiB
Markdown
---
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id: 5900f4931000cf542c50ffa5
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challengeType: 5
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title: 'Problem 294: Sum of digits - experience #23'
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forumTopicId: 301946
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---
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## Description
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<section id='description'>
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For a positive integer k, define d(k) as the sum of the digits of k in its usual decimal representation.
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Thus d(42) = 4+2 = 6.
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For a positive integer n, define S(n) as the number of positive integers k < 10n with the following properties :
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k is divisible by 23 and
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d(k) = 23.
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You are given that S(9) = 263626 and S(42) = 6377168878570056.
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Find S(1112) and give your answer mod 109.
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</section>
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## Instructions
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<section id='instructions'>
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</section>
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## Tests
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<section id='tests'>
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```yml
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tests:
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- text: <code>euler294()</code> should return 789184709.
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testString: assert.strictEqual(euler294(), 789184709);
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```
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</section>
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## Challenge Seed
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<section id='challengeSeed'>
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<div id='js-seed'>
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```js
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function euler294() {
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// Good luck!
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return true;
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}
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euler294();
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```
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</div>
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</section>
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## Solution
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<section id='solution'>
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```js
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// solution required
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```
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</section>
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