2018-10-10 22:03:03 +00:00
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---
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id: 5900f4a11000cf542c50ffb3
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challengeType: 5
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videoUrl: ''
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2020-10-01 15:54:21 +00:00
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title: 问题308:惊人的生成素数的自动机
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2018-10-10 22:03:03 +00:00
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---
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## Description
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2020-02-17 16:40:55 +00:00
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<section id="description">
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用编程语言Fractran编写的程序包含一个分数列表。
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Fractran虚拟机的内部状态是一个正整数,该整数最初设置为种子值。 Fractran程序的每次迭代都将状态整数乘以列表中的第一个分数,从而将其保留为整数。
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例如,约翰·霍顿·康威(John Horton Conway)为黄金一代编写的Fractran程序之一,由以下14个部分组成:1791
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,
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7885
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,
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1951年
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,
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2338
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,
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2933
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,
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7729
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,
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9523
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,
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7719
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,
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117
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,
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1113
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,
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1311
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,
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152
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,
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17
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,
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551
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。
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从种子整数2开始,程序的连续迭代产生以下序列:
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15,825,725,1925,2275,425,...,68,4,30,...,136,8,60,...,544,32,240,...
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此序列中出现的2的幂是22、23、25,...
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可以证明,该序列中所有2的幂都具有质数指数,并且所有质数都以正确的顺序显示为2的幂指数!
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如果有人使用上面的Fractran程序来解决Project Euler问题7(找到第10001个素数),那么在该程序产生第210001个素数之前,将需要进行几次迭代?
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</section>
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2018-10-10 22:03:03 +00:00
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## Instructions
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2020-02-17 16:40:55 +00:00
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<section id="instructions">
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</section>
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2018-10-10 22:03:03 +00:00
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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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2020-02-17 16:40:55 +00:00
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- text: <code>euler308()</code>应该返回1539669807660924。
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testString: assert.strictEqual(euler308(), 1539669807660924);
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2018-10-10 22:03:03 +00:00
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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 euler308() {
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// Good luck!
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return true;
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}
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euler308();
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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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2020-08-13 15:24:35 +00:00
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/section>
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