43 lines
759 B
Markdown
43 lines
759 B
Markdown
---
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id: 5900f3f11000cf542c50ff03
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title: 'Problem 132: Large repunit factors'
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challengeType: 5
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forumTopicId: 301760
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dashedName: problem-132-large-repunit-factors
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---
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# --description--
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A number consisting entirely of ones is called a repunit. We shall define $R(k)$ to be a repunit of length $k$.
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For example, $R(10) = 1111111111 = 11 × 41 × 271 × 9091$, and the sum of these prime factors is 9414.
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Find the sum of the first forty prime factors of $R({10}^9)$.
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# --hints--
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`largeRepunitFactors()` should return `843296`.
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```js
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assert.strictEqual(largeRepunitFactors(), 843296);
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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 largeRepunitFactors() {
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return true;
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}
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largeRepunitFactors();
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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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