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
881 B
Markdown
43 lines
881 B
Markdown
---
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id: 5900f5311000cf542c510042
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title: 问题451：模逆
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challengeType: 5
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videoUrl: ''
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dashedName: problem-451-modular-inverses
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---
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# --description--
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考虑数字15.有八个正数小于15，它们与15：1,2,4,7,8,11,13,14相互作用。这些数模15的模数逆是：1,8,4 ，13,2,11,7,14因为1 \* 1 mod 15 = 1 2 \* 8 = 16 mod 15 = 1 4 \* 4 = 16 mod 15 = 1 7 \* 13 = 91 mod 15 = 1 11 \* 11 = 121 mod 15 = 1 14 \* 14 = 196 mod 15 = 1
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设I（n）是小于n-1的最大正数m，使得m modulo n的模逆与m本身相等。所以我（15）= 11。我（100）= 51和I（7）= 1。
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求3Σn≤2·107的ΣI（n）
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# --hints--
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`euler451()`应该返回153651073760956。
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```js
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assert.strictEqual(euler451(), 153651073760956);
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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 euler451() {
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return true;
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}
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euler451();
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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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