67 lines
962 B
Markdown
67 lines
962 B
Markdown
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---
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id: 5900f3e81000cf542c50fefb
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title: 'Problem 124: Ordered radicals'
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challengeType: 5
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forumTopicId: 301751
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dashedName: problem-124-ordered-radicals
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---
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# --description--
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The radical of n, rad(n), is the product of the distinct prime factors of n. For example, 504 = 23 × 32 × 7, so rad(504) = 2 × 3 × 7 = 42.
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If we calculate rad(n) for 1 ≤ n ≤ 10, then sort them on rad(n), and sorting on n if the radical values are equal, we get:
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Unsorted
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Sorted n rad(n)
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n rad(n) k 11
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111 22
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222 33
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423 42
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824 55
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335 66
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936 77
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557 82
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668 93
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779 1010
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101010 Let E(k) be the kth element in the sorted n column; for example, E(4) = 8 and E(6) = 9. If rad(n) is sorted for 1 ≤ n ≤ 100000, find E(10000).
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# --hints--
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`euler124()` should return 21417.
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```js
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assert.strictEqual(euler124(), 21417);
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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 euler124() {
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return true;
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}
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euler124();
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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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