1.1 KiB
1.1 KiB
id | challengeType | title | forumTopicId |
---|---|---|---|
5900f49d1000cf542c50ffb0 | 5 | Problem 305: Reflexive Position | 301959 |
Description
It's easy to see that any number will show up an infinite number of times in S.
Let's call f(n) the starting position of the nth occurrence of n in S. For example, f(1)=1, f(5)=81, f(12)=271 and f(7780)=111111365.
Find ∑f(3k) for 1≤k≤13.
Instructions
Tests
tests:
- text: <code>euler305()</code> should return 18174995535140.
testString: assert.strictEqual(euler305(), 18174995535140);
Challenge Seed
function euler305() {
// Good luck!
return true;
}
euler305();
Solution
// solution required