47 lines
947 B
Markdown
47 lines
947 B
Markdown
---
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id: 5900f5411000cf542c510053
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title: 'Problem 469: Empty chairs'
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challengeType: 5
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forumTopicId: 302144
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dashedName: problem-469-empty-chairs
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---
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# --description--
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In a room N chairs are placed around a round table.
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Knights enter the room one by one and choose at random an available empty chair.
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To have enough elbow room the knights always leave at least one empty chair between each other.
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When there aren't any suitable chairs left, the fraction C of empty chairs is determined. We also define E(N) as the expected value of C. We can verify that E(4) = 1/2 and E(6) = 5/9.
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Find E(1018). Give your answer rounded to fourteen decimal places in the form 0.abcdefghijklmn.
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# --hints--
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`euler469()` should return 0.56766764161831.
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```js
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assert.strictEqual(euler469(), 0.56766764161831);
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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 euler469() {
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return true;
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}
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euler469();
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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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