2018-10-10 22:03:03 +00:00
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---
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id: 5900f5411000cf542c510054
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2020-12-16 07:37:30 +00:00
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title: 问题468:二项式系数的平滑除数
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2018-10-10 22:03:03 +00:00
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challengeType: 5
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videoUrl: ''
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2021-01-13 02:31:00 +00:00
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dashedName: problem-468-smooth-divisors-of-binomial-coefficients
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2018-10-10 22:03:03 +00:00
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---
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2020-12-16 07:37:30 +00:00
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# --description--
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2018-10-10 22:03:03 +00:00
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2020-12-16 07:37:30 +00:00
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如果没有一个整数因子大于B,则整数称为B-smooth。
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2018-10-10 22:03:03 +00:00
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2020-12-16 07:37:30 +00:00
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设SB(n)是n的最大B-平滑除数。示例:S1(10)= 1 S4(2100)= 12 S17(2496144)= 5712
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2018-10-10 22:03:03 +00:00
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2020-12-16 07:37:30 +00:00
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定义F(n)=Σ1≤B≤nΣ0≤r≤nSB(C(n,r))。这里,C(n,r)表示二项式系数。示例:F(11)= 3132 F(1 111)mod 1 000 000 993 = 706036312 F(111 111)mod 1 000 000 993 = 22156169
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2018-10-10 22:03:03 +00:00
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2020-12-16 07:37:30 +00:00
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求F(11 111 111)mod 1 000 000 993。
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2018-10-10 22:03:03 +00:00
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2020-12-16 07:37:30 +00:00
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# --hints--
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2018-10-10 22:03:03 +00:00
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2020-12-16 07:37:30 +00:00
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`euler468()`应该返回852950321。
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2018-10-10 22:03:03 +00:00
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```js
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2020-12-16 07:37:30 +00:00
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assert.strictEqual(euler468(), 852950321);
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2018-10-10 22:03:03 +00:00
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```
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2021-01-13 02:31:00 +00:00
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# --seed--
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## --seed-contents--
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```js
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function euler468() {
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return true;
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}
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euler468();
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```
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2020-12-16 07:37:30 +00:00
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# --solutions--
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2020-08-13 15:24:35 +00:00
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2021-01-13 02:31:00 +00:00
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```js
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// solution required
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```
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