7d9496e52c
* fix: clean-up Project Euler 361-380 * fix: improve wording Co-authored-by: Sem Bauke <46919888+Sembauke@users.noreply.github.com> * fix: remove unnecessary paragraph * fix: corrections from review Co-authored-by: Tom <20648924+moT01@users.noreply.github.com> Co-authored-by: Sem Bauke <46919888+Sembauke@users.noreply.github.com> Co-authored-by: Tom <20648924+moT01@users.noreply.github.com>
45 lines
841 B
Markdown
45 lines
841 B
Markdown
---
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id: 5900f4e81000cf542c50fffa
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title: 'Problem 379: Least common multiple count'
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challengeType: 5
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forumTopicId: 302041
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dashedName: problem-379-least-common-multiple-count
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---
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# --description--
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Let $f(n)$ be the number of couples ($x$, $y$) with $x$ and $y$ positive integers, $x ≤ y$ and the least common multiple of $x$ and $y$ equal to $n$.
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Let $g$ be the summatory function of $f$, i.e.: $g(n) = \sum f(i)$ for $1 ≤ i ≤ n$.
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You are given that $g({10}^6) = 37\\,429\\,395$.
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Find $g({10}^{12})$.
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# --hints--
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`leastCommonMultipleCount()` should return `132314136838185`.
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```js
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assert.strictEqual(leastCommonMultipleCount(), 132314136838185);
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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 leastCommonMultipleCount() {
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return true;
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}
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leastCommonMultipleCount();
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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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