49 lines
741 B
Markdown
49 lines
741 B
Markdown
---
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id: 5900f5271000cf542c51003a
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title: 'Problem 443: GCD sequence'
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challengeType: 5
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forumTopicId: 302115
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dashedName: problem-443-gcd-sequence
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---
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# --description--
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Let g(n) be a sequence defined as follows: g(4) = 13, g(n) = g(n-1) + gcd(n, g(n-1)) for n > 4.
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The first few values are:
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n 4567891011121314151617181920... g(n) 1314161718272829303132333451545560...
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<!-- TODO Use MathJax -->
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You are given that g(1 000) = 2524 and g(1 000 000) = 2624152.
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Find g(1015).
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# --hints--
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`euler443()` should return 2744233049300770.
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```js
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assert.strictEqual(euler443(), 2744233049300770);
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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 euler443() {
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return true;
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}
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euler443();
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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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