bfc21e4c40
* fix: clean-up Project Euler 141-160 * fix: corrections from review Co-authored-by: Sem Bauke <46919888+Sembauke@users.noreply.github.com> * fix: corrections from review Co-authored-by: Tom <20648924+moT01@users.noreply.github.com> * fix: use different notation for consistency * Update curriculum/challenges/english/10-coding-interview-prep/project-euler/problem-144-investigating-multiple-reflections-of-a-laser-beam.md Co-authored-by: gikf <60067306+gikf@users.noreply.github.com> Co-authored-by: Sem Bauke <46919888+Sembauke@users.noreply.github.com> Co-authored-by: Tom <20648924+moT01@users.noreply.github.com>
55 lines
1.0 KiB
Markdown
55 lines
1.0 KiB
Markdown
---
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id: 5900f4021000cf542c50ff14
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title: 'Problem 148: Exploring Pascal''s triangle'
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challengeType: 5
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forumTopicId: 301777
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dashedName: problem-148-exploring-pascals-triangle
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---
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# --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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```
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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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```
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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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# --instructions--
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Find the number of entries which are not divisible by 7 in the first one billion (${10}^9$) rows of Pascal's triangle.
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# --hints--
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`entriesOfPascalsTriangle()` should return `2129970655314432`.
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```js
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assert.strictEqual(entriesOfPascalsTriangle(), 2129970655314432);
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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 entriesOfPascalsTriangle() {
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return true;
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}
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entriesOfPascalsTriangle();
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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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