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>
43 lines
907 B
Markdown
43 lines
907 B
Markdown
---
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id: 5900f4711000cf542c50ff84
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title: 'Problem 261: Pivotal Square Sums'
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challengeType: 5
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forumTopicId: 301910
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dashedName: problem-261-pivotal-square-sums
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---
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# --description--
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Let us call a positive integer k a square-pivot, if there is a pair of integers m > 0 and n ≥ k, such that the sum of the (m+1) consecutive squares up to k equals the sum of the m consecutive squares from (n+1) on:
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(k-m)2 + ... + k2 = (n+1)2 + ... + (n+m)2.
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Some small square-pivots are 4: 32 + 42 = 52 21: 202 + 212 = 292 24: 212 + 222 + 232 + 242 = 252 + 262 + 272 110: 1082 + 1092 + 1102 = 1332 + 1342Find the sum of all distinct square-pivots ≤ 1010.
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# --hints--
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`euler261()` should return 238890850232021.
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```js
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assert.strictEqual(euler261(), 238890850232021);
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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 euler261() {
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return true;
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}
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euler261();
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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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