69 lines
1.1 KiB
Markdown
69 lines
1.1 KiB
Markdown
---
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id: 5900f4021000cf542c50ff14
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challengeType: 5
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title: 'Problem 148: Exploring Pascal''s triangle'
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forumTopicId: 301777
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---
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## Description
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<section id='description'>
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We can easily verify that none of the entries in the first seven rows of Pascal's triangle are divisible by 7:
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<pre>
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1
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1 1
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1 2 1
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1 3 3 1
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1 4 6 4 1
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1 5 10 10 5 1
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1 6 15 20 15 6 1
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</pre>
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However, if we check the first one hundred rows, we will find that only 2361 of the 5050 entries are not divisible by 7.
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</section>
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## Instructions
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<section id='instructions'>
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Find the number of entries which are not divisible by 7 in the first one billion (10<sup>9</sup>) rows of Pascal's triangle.
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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>euler148()</code> should return 2129970655314432.
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testString: assert.strictEqual(euler148(), 2129970655314432);
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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 euler148() {
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return true;
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}
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euler148();
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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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