2018-09-30 22:01:58 +00:00
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---
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id: 5900f3f11000cf542c50ff03
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title: 'Problem 132: Large repunit factors'
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2020-11-27 18:02:05 +00:00
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challengeType: 5
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2019-08-05 16:17:33 +00:00
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forumTopicId: 301760
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2021-01-13 02:31:00 +00:00
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dashedName: problem-132-large-repunit-factors
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2018-09-30 22:01:58 +00:00
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---
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2020-11-27 18:02:05 +00:00
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# --description--
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2018-09-30 22:01:58 +00:00
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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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2020-11-27 18:02:05 +00:00
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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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2018-09-30 22:01:58 +00:00
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2020-11-27 18:02:05 +00:00
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Find the sum of the first forty prime factors of R(109).
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2018-09-30 22:01:58 +00:00
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2020-11-27 18:02:05 +00:00
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# --hints--
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2018-09-30 22:01:58 +00:00
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2020-11-27 18:02:05 +00:00
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`euler132()` should return 843296.
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2018-09-30 22:01:58 +00:00
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2020-11-27 18:02:05 +00:00
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```js
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assert.strictEqual(euler132(), 843296);
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2018-09-30 22:01:58 +00:00
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```
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2020-11-27 18:02:05 +00:00
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# --seed--
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2018-09-30 22:01:58 +00:00
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2020-11-27 18:02:05 +00:00
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## --seed-contents--
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2018-09-30 22:01:58 +00:00
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```js
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function euler132() {
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2020-09-15 16:57:40 +00:00
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2018-09-30 22:01:58 +00:00
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return true;
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}
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euler132();
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```
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2020-11-27 18:02:05 +00:00
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# --solutions--
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2018-09-30 22:01:58 +00:00
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```js
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// solution required
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```
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