62 lines
2.0 KiB
Markdown
62 lines
2.0 KiB
Markdown
---
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id: 5900f3871000cf542c50fe9a
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challengeType: 5
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title: 'Problem 27: Quadratic primes'
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videoUrl: ''
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localeTitle: 问题27:二次素数
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---
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## Description
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<section id="description">欧拉发现了显着的二次公式:$ n ^ 2 + n + 41 $事实证明,公式将为连续的整数值$ 0 \ le n \ le 39 $产生40个素数。但是,当$ n = 40时,40 ^ 2 + 40 + 41 = 40(40 + 1)+ 41 $可被41整除,当然$ n = 41时,41 ^ 2 + 41 + 41 $显然可以被整除41.发现了令人难以置信的公式$ n ^ 2 - 79n + 1601 $,它为连续值$ 0 \ le n \ le 79 $产生80个素数。系数-79和1601的乘积是-126479。考虑形式的二次方: <p> $ n ^ 2 + an + b $,其中$ | a | <range $和$ | b | \ le $ $其中$ | n | $是$ n $的模数/绝对值,例如$ | 11 | = 11 $和$ | -4 | = 4 $ </p><p>找到系数的乘积,$ a $和$ b $,用于生成连续值$ n $的最大素数数的二次表达式,从$ n = 0 $开始。 </p></section>
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## Instructions
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<section id="instructions">
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</section>
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## Tests
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<section id='tests'>
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```yml
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tests:
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- text: <code>quadraticPrimes(200)</code>应返回-4925。
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testString: 'assert(quadraticPrimes(200) == -4925, "<code>quadraticPrimes(200)</code> should return -4925.");'
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- text: <code>quadraticPrimes(500)</code>应返回-18901。
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testString: 'assert(quadraticPrimes(500) == -18901, "<code>quadraticPrimes(500)</code> should return -18901.");'
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- text: <code>quadraticPrimes(800)</code>应返回-43835。
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testString: 'assert(quadraticPrimes(800) == -43835, "<code>quadraticPrimes(800)</code> should return -43835.");'
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- text: <code>quadraticPrimes(1000)</code>应返回-59231。
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testString: 'assert(quadraticPrimes(1000) == -59231, "<code>quadraticPrimes(1000)</code> should return -59231.");'
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```
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</section>
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## Challenge Seed
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<section id='challengeSeed'>
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<div id='js-seed'>
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```js
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function quadraticPrimes(range) {
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// Good luck!
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return range;
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}
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quadraticPrimes(1000);
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```
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</div>
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</section>
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## Solution
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<section id='solution'>
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```js
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// solution required
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```
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</section>
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