2018-10-10 18:03:03 -04:00
---
id: 5900f4ea1000cf542c50fffc
challengeType: 5
title: 'Problem 381: (prime-k) factorial'
2019-08-28 16:26:13 +03:00
forumTopicId: 302045
localeTitle: 'Problem 381: (prime-k) factorial'
2018-10-10 18:03:03 -04:00
---
## Description
2019-08-28 16:26:13 +03:00
< section id = 'description' >
Для простого p пусть S (p) = (Σ (pk)!) Mod (p) для 1 ≤ k ≤ 5. < p > Например, если p = 7, (7-1)! + (7-2)! + (7-3)! + (7-4)! + (7-5)! = 6! + 5! + 4! + 3! + 2! = 720 + 120 + 24 + 6 + 2 = 872. Так как 872 mod (7) = 4, S (7) = 4. < / p > < p > Можно проверить, что ΣS (p) = 480 для 5 ≤ p < 100. < / p > < p > Найти ΣS (p) для 5 ≤ p < 108. < / p >
< / section >
2018-10-10 18:03:03 -04:00
## Instructions
2019-08-28 16:26:13 +03:00
< section id = 'instructions' >
< / section >
2018-10-10 18:03:03 -04:00
## Tests
< section id = 'tests' >
```yml
tests:
2019-08-28 16:26:13 +03:00
- text: < code > euler381()</ code > should return 139602943319822.
testString: assert.strictEqual(euler381(), 139602943319822);
2018-10-10 18:03:03 -04:00
```
< / section >
## Challenge Seed
< section id = 'challengeSeed' >
< div id = 'js-seed' >
```js
function euler381() {
// Good luck!
return true;
}
euler381();
```
< / div >
< / section >
## Solution
< section id = 'solution' >
```js
// solution required
```
2019-08-28 16:26:13 +03:00
2018-10-10 18:03:03 -04:00
< / section >