2018-09-30 23:01:58 +01:00
										 
									 
								 
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								id: 5900f53a1000cf542c51004c
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								challengeType: 5
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								title: 'Problem 461: Almost Pi'
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								---
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								## Description
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								<section id='description'>
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								Let fn(k) = ek/n - 1, for all non-negative integers k.
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								Remarkably, f200(6) + f200(75) + f200(89) + f200(226) = 3.141592644529… ≈ π.
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								In fact, it is the best approximation of π of the form fn(a) + fn(b) + fn(c) + fn(d) for n = 200.
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								Let g(n) = a2 + b2 + c2 + d 2 for a, b, c, d that minimize the error: | fn(a) + fn(b) + fn(c) + fn(d) - π|
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								(where |x| denotes the absolute value of x).
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								You are given g(200) = 62 + 752 + 892 + 2262 = 64658.
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								Find g(10000).
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								</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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											2018-10-04 14:37:37 +01:00
										 
									 
								 
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								tests:
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								  - text: <code>euler461()</code> should return 159820276.
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											2018-10-20 21:02:47 +03:00
										 
									 
								 
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								    testString: assert.strictEqual(euler461(), 159820276, '<code>euler461()</code> should return 159820276.');
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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 euler461() {
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								  // Good luck!
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								  return true;
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								}
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								euler461();
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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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