1.3 KiB
1.3 KiB
id | challengeType | title | forumTopicId |
---|---|---|---|
5900f4291000cf542c50ff3c | 5 | Problem 189: Tri-colouring a triangular grid | 301825 |
Description
We wish to colour the interior of each triangle with one of three colours: red, green or blue, so that no two neighbouring triangles have the same colour. Such a colouring shall be called valid. Here, two triangles are said to be neighbouring if they share an edge. Note: if they only share a vertex, then they are not neighbours.
For example, here is a valid colouring of the above grid:
A colouring C' which is obtained from a colouring C by rotation or reflection is considered distinct from C unless the two are identical.
How many distinct valid colourings are there for the above configuration?
Instructions
Tests
tests:
- text: <code>euler189()</code> should return 10834893628237824.
testString: assert.strictEqual(euler189(), 10834893628237824);
Challenge Seed
function euler189() {
// Good luck!
return true;
}
euler189();
Solution
// solution required