43 lines
865 B
Markdown
43 lines
865 B
Markdown
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---
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id: 5900f4de1000cf542c50fff0
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title: 'Problem 369: Badugi'
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challengeType: 5
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forumTopicId: 302030
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dashedName: problem-369-badugi
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---
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# --description--
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In a standard 52 card deck of playing cards, a set of 4 cards is a Badugi if it contains 4 cards with no pairs and no two cards of the same suit.
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Let $f(n)$ be the number of ways to choose $n$ cards with a 4 card subset that is a Badugi. For example, there are $2\\,598\\,960$ ways to choose five cards from a standard 52 card deck, of which $514\\,800$ contain a 4 card subset that is a Badugi, so $f(5) = 514800$.
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Find $\sum f(n)$ for $4 ≤ n ≤ 13$.
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# --hints--
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`badugi()` should return `862400558448`.
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```js
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assert.strictEqual(badugi(), 862400558448);
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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 badugi() {
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return true;
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}
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badugi();
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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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