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>
45 lines
922 B
Markdown
45 lines
922 B
Markdown
---
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id: 5900f3ef1000cf542c50ff01
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title: 'Problem 129: Repunit divisibility'
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challengeType: 5
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forumTopicId: 301756
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dashedName: problem-129-repunit-divisibility
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---
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# --description--
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A number consisting entirely of ones is called a repunit. We shall define R(k) to be a repunit of length k; for example, R(6) = 111111.
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Given that n is a positive integer and GCD(n, 10) = 1, it can be shown that there always exists a value, k, for which R(k) is divisible by n, and let A(n) be the least such value of k; for example, A(7) = 6 and A(41) = 5.
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The least value of n for which A(n) first exceeds ten is 17.
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Find the least value of n for which A(n) first exceeds one-million.
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# --hints--
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`euler129()` should return 1000023.
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```js
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assert.strictEqual(euler129(), 1000023);
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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 euler129() {
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return true;
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}
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euler129();
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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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