2018-10-10 18:03:03 -04:00
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---
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id: 5900f4ed1000cf542c50ffff
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2020-12-16 00:37:30 -07:00
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title: 问题383:阶乘之间的可比性比较
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2018-10-10 18:03:03 -04:00
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challengeType: 5
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videoUrl: ''
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2021-01-13 03:31:00 +01:00
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dashedName: problem-383-divisibility-comparison-between-factorials
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2018-10-10 18:03:03 -04:00
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---
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2020-12-16 00:37:30 -07:00
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# --description--
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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设f5(n)是最大整数x,其中5x除以n。例如,f5(625000)= 7。
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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令T5(n)为满足f5((2·i-1)!)<2·f5(i!)且1≤i≤n的整数i。可以证实T5(103)= 68并且T5(109)= 2408210。
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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找到T5(1018)。
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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# --hints--
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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`euler383()`应该返回22173624649806。
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2018-10-10 18:03:03 -04:00
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```js
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2020-12-16 00:37:30 -07:00
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assert.strictEqual(euler383(), 22173624649806);
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2018-10-10 18:03:03 -04:00
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```
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2021-01-13 03:31:00 +01:00
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# --seed--
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## --seed-contents--
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```js
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function euler383() {
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return true;
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}
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euler383();
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```
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2020-12-16 00:37:30 -07:00
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# --solutions--
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2020-08-13 17:24:35 +02:00
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2021-01-13 03:31:00 +01:00
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```js
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// solution required
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```
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