43 lines
695 B
Markdown
43 lines
695 B
Markdown
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---
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id: 5900f4d01000cf542c50ffe2
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title: 'Problem 355: Maximal coprime subset'
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challengeType: 5
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forumTopicId: 302015
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dashedName: problem-355-maximal-coprime-subset
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---
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# --description--
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Define Co(n) to be the maximal possible sum of a set of mutually co-prime elements from {1, 2, ..., n}. For example Co(10) is 30 and hits that maximum on the subset {1, 5, 7, 8, 9}.
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You are given that Co(30) = 193 and Co(100) = 1356.
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Find Co(200000).
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# --hints--
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`euler355()` should return 1726545007.
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```js
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assert.strictEqual(euler355(), 1726545007);
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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 euler355() {
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return true;
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}
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euler355();
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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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