ee1e8abd87
* feat(tools): add seed/solution restore script * chore(curriculum): remove empty sections' markers * chore(curriculum): add seed + solution to Chinese * chore: remove old formatter * fix: update getChallenges parse translated challenges separately, without reference to the source * chore(curriculum): add dashedName to English * chore(curriculum): add dashedName to Chinese * refactor: remove unused challenge property 'name' * fix: relax dashedName requirement * fix: stray tag Remove stray `pre` tag from challenge file. Signed-off-by: nhcarrigan <nhcarrigan@gmail.com> Co-authored-by: nhcarrigan <nhcarrigan@gmail.com>
47 lines
900 B
Markdown
47 lines
900 B
Markdown
---
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id: 5900f4c41000cf542c50ffd6
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title: 问题343：分数序列
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challengeType: 5
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videoUrl: ''
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dashedName: problem-343-fractional-sequences
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---
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# --description--
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对于任何正整数k，分数xi / yi的有限序列ai由以下定义：a1 = 1 / k且ai =（xi-1 + 1）/（yi-1-1）减少到最低项i> 1 。当ai达到某个整数n时，序列停止。 （即，当yi = 1时。）定义f（k）= n。例如，对于k = 20：
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1/20→2/19→3/18 = 1/6→2/5→3/4→4/3→5/2→6/1 = 6
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所以f（20）= 6。
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对于1≤k≤100，f（1）= 1，f（2）= 2，f（3）= 1且Σf（k3）= 118937。
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找Σf（k3）为1≤k≤2×106。
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# --hints--
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`euler343()`应该返回269533451410884200。
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```js
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assert.strictEqual(euler343(), 269533451410884200);
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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 euler343() {
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return true;
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}
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euler343();
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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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