1.3 KiB
1.3 KiB
id | challengeType | title |
---|---|---|
5900f50a1000cf542c51001c | 5 | Problem 413: One-child Numbers |
Description
For example, 5671 is a 4-digit one-child number. Among all its sub-strings 5, 6, 7, 1, 56, 67, 71, 567, 671 and 5671, only 56 is divisible by 4. Similarly, 104 is a 3-digit one-child number because only 0 is divisible by 3. 1132451 is a 7-digit one-child number because only 245 is divisible by 7.
Let F(N) be the number of the one-child numbers less than N. We can verify that F(10) = 9, F(103) = 389 and F(107) = 277674.
Find F(1019).
Instructions
Tests
tests:
- text: <code>euler413()</code> should return 3079418648040719.
testString: assert.strictEqual(euler413(), 3079418648040719, '<code>euler413()</code> should return 3079418648040719.');
Challenge Seed
function euler413() {
// Good luck!
return true;
}
euler413();
Solution
// solution required