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								id: 5900f44b1000cf542c50ff5e
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								title: 'Problem 223: Almost right-angled triangles I'
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								challengeType: 5
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											2019-08-05 09:17:33 -07:00
										 
									 
								 
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								forumTopicId: 301866
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								dashedName: problem-223-almost-right-angled-triangles-i
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								---
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								# --description--
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											2021-07-15 14:26:34 +02:00
										 
									 
								 
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								Let us call an integer sided triangle with sides $a ≤ b ≤ c$ barely acute if the sides satisfy $a^2 + b^2 = c^2 + 1$.
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								How many barely acute triangles are there with perimeter $≤ 25\\,000\\,000$?
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								# --hints--
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								`almostRightAngledTrianglesOne()` should return `61614848`.
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								```js
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								assert.strictEqual(almostRightAngledTrianglesOne(), 61614848);
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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 almostRightAngledTrianglesOne() {
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								  return true;
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								}
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								almostRightAngledTrianglesOne();
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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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