47 lines
977 B
Markdown
47 lines
977 B
Markdown
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---
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id: 5900f4a51000cf542c50ffb7
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title: 'Problem 312: Cyclic paths on Sierpiński graphs'
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challengeType: 5
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forumTopicId: 301968
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dashedName: problem-312-cyclic-paths-on-sierpiski-graphs
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---
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# --description--
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\- A Sierpiński graph of order-1 (S1) is an equilateral triangle.
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\- Sn+1 is obtained from Sn by positioning three copies of Sn so that every pair of copies has one common corner.
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Let C(n) be the number of cycles that pass exactly once through all the vertices of Sn. For example, C(3) = 8 because eight such cycles can be drawn on S3, as shown below:
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It can also be verified that : C(1) = C(2) = 1 C(5) = 71328803586048 C(10 000) mod 108 = 37652224 C(10 000) mod 138 = 617720485
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Find C(C(C(10 000))) mod 138.
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# --hints--
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`euler312()` should return 324681947.
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```js
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assert.strictEqual(euler312(), 324681947);
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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 euler312() {
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return true;
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}
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euler312();
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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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