45 lines
761 B
Markdown
45 lines
761 B
Markdown
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---
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id: 5900f3e71000cf542c50fefa
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title: 'Problem 123: Prime square remainders'
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challengeType: 5
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forumTopicId: 301750
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dashedName: problem-123-prime-square-remainders
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---
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# --description--
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Let pn be the nth prime: 2, 3, 5, 7, 11, ..., and let r be the remainder when (pn−1)n + (pn+1)n is divided by pn2.
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For example, when n = 3, p3 = 5, and 43 + 63 = 280 ≡ 5 mod 25.
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The least value of n for which the remainder first exceeds 109 is 7037.
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Find the least value of n for which the remainder first exceeds 1010.
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# --hints--
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`euler123()` should return 21035.
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```js
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assert.strictEqual(euler123(), 21035);
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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 euler123() {
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return true;
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}
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euler123();
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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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