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
883 B
Markdown
47 lines
883 B
Markdown
---
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id: 5900f4ef1000cf542c510001
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title: 'Problem 386: Maximum length of an antichain'
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challengeType: 5
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forumTopicId: 302050
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dashedName: problem-386-maximum-length-of-an-antichain
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---
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# --description--
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Let n be an integer and S(n) be the set of factors of n.
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A subset A of S(n) is called an antichain of S(n) if A contains only one element or if none of the elements of A divides any of the other elements of A.
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For example: S(30) = {1, 2, 3, 5, 6, 10, 15, 30} {2, 5, 6} is not an antichain of S(30). {2, 3, 5} is an antichain of S(30).
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Let N(n) be the maximum length of an antichain of S(n).
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Find ΣN(n) for 1 ≤ n ≤ 108
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# --hints--
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`euler386()` should return 528755790.
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```js
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assert.strictEqual(euler386(), 528755790);
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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 euler386() {
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return true;
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}
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euler386();
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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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