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>
45 lines
1016 B
Markdown
45 lines
1016 B
Markdown
---
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id: 5900f45f1000cf542c50ff71
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title: 问题242：奇数三胞胎
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challengeType: 5
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videoUrl: ''
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dashedName: problem-242-odd-triplets
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---
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# --description--
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给定集合{1,2，...，n}，我们将f（n，k）定义为具有奇数元素之和的k元素子集的数量。例如，f（5,3）= 4，因为集合{1,2,3,4,5}有四个3元素子集具有奇数元素，即：{1,2,4}，{ 1,3,5}，{2,3,4}和{2,4,5}。
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当所有三个值n，k和f（n，k）都是奇数时，我们说它们产生奇数三元组\[n，k，f（n，k）]。
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正好有五个奇数三元组，n≤10，即：\[1,1，f（1,1）= 1]，\[5,1，f（5,1）= 3]，\[5,5，f （5,5）= 1]，\[9,1，f（9,1）= 5]和\[9,9，f（9,9）= 1]。
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n≤1012，有多少奇数三胞胎？
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# --hints--
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`euler242()`应该返回997104142249036700。
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```js
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assert.strictEqual(euler242(), 997104142249036700);
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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 euler242() {
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return true;
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}
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euler242();
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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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