2021-05-05 10:13:49 -07:00
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---
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id: 5900f3f11000cf542c50ff03
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2021-11-17 03:53:39 -08:00
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title: '問題 132:大純元數因子'
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2021-05-05 10:13:49 -07:00
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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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2021-11-17 03:53:39 -08:00
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完全由 1 組成的數字稱爲純元數(repunit)。 我們定義 $R(k)$ 爲長度 $k$ 的純元數。
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2021-05-05 10:13:49 -07:00
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2021-11-17 03:53:39 -08:00
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例如 $R(10) = 1111111111 = 11 × 41 × 271 × 9091$,則其素數因子的和爲 9414。
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2021-11-17 03:53:39 -08:00
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求 $R({10}^9)$ 的前 40 個素數因子的和。
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# --hints--
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2021-11-17 03:53:39 -08:00
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`largeRepunitFactors()` 應該返回 `843296`。
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2021-05-05 10:13:49 -07:00
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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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2021-11-17 03:53:39 -08:00
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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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