43 lines
		
	
	
		
			1021 B
		
	
	
	
		
			Markdown
		
	
	
	
	
	
			
		
		
	
	
			43 lines
		
	
	
		
			1021 B
		
	
	
	
		
			Markdown
		
	
	
	
	
	
---
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id: 5900f41a1000cf542c50ff2c
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title: >-
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  Problem 173: Using up to one million tiles how many different "hollow" square laminae can be formed?
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challengeType: 5
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forumTopicId: 301808
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dashedName: >-
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  problem-173-using-up-to-one-million-tiles-how-many-different-hollow-square-laminae-can-be-formed
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---
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# --description--
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We shall define a square lamina to be a square outline with a square "hole" so that the shape possesses vertical and horizontal symmetry. For example, using exactly thirty-two square tiles we can form two different square laminae:
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With one-hundred tiles, and not necessarily using all of the tiles at one time, it is possible to form forty-one different square laminae. Using up to one million tiles how many different square laminae can be formed?
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# --hints--
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`euler173()` should return 1572729.
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```js
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assert.strictEqual(euler173(), 1572729);
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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 euler173() {
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  return true;
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}
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euler173();
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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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