freeCodeCamp/curriculum/challenges/english/10-coding-interview-prep/project-euler/problem-448-average-least-c...

---
id: 5900f52c1000cf542c51003f
title: 'Problem 448: Average least common multiple'
challengeType: 5
forumTopicId: 302120
dashedName: problem-448-average-least-common-multiple
---

# --description--

The function lcm(a,b) denotes the least common multiple of a and b.

Let A(n) be the average of the values of lcm(n,i) for 1≤i≤n.

E.g: A(2)=(2+2)/2=2 and A(10)=(10+10+30+20+10+30+70+40+90+10)/10=32.

Let S(n)=∑A(k) for 1≤k≤n. S(100)=122726.

Find S(99999999019) mod 999999017.

# --hints--

`euler448()` should return 106467648.

```js
assert.strictEqual(euler448(), 106467648);
```

# --seed--

## --seed-contents--

```js
function euler448() {

  return true;
}

euler448();
```

# --solutions--

```js
// solution required
```
feat(challenge-md): Add initial markdown challenge files 2018-09-30 22:01:58 +00:00			`---`
			`id: 5900f52c1000cf542c51003f`
			`title: 'Problem 448: Average least common multiple'`
Feat: add new Markdown parser (#39800) and change all the challenges to new `md` format. 2020-11-27 18:02:05 +00:00			`challengeType: 5`
fix(curriculum): Added forumTopicId to remaining 1200 challeng… (#36558) 2019-08-05 16:17:33 +00:00			`forumTopicId: 302120`
feat(curriculum): restore seed + solution to Chinese (#40683) * feat(tools): add seed/solution restore script * chore(curriculum): remove empty sections' markers * chore(curriculum): add seed + solution to Chinese * chore: remove old formatter * fix: update getChallenges parse translated challenges separately, without reference to the source * chore(curriculum): add dashedName to English * chore(curriculum): add dashedName to Chinese * refactor: remove unused challenge property 'name' * fix: relax dashedName requirement * fix: stray tag Remove stray `pre` tag from challenge file. Signed-off-by: nhcarrigan <nhcarrigan@gmail.com> Co-authored-by: nhcarrigan <nhcarrigan@gmail.com> 2021-01-13 02:31:00 +00:00			`dashedName: problem-448-average-least-common-multiple`
feat(challenge-md): Add initial markdown challenge files 2018-09-30 22:01:58 +00:00			`---`

Feat: add new Markdown parser (#39800) and change all the challenges to new `md` format. 2020-11-27 18:02:05 +00:00			`# --description--`

feat(challenge-md): Add initial markdown challenge files 2018-09-30 22:01:58 +00:00			`The function lcm(a,b) denotes the least common multiple of a and b.`
Feat: add new Markdown parser (#39800) and change all the challenges to new `md` format. 2020-11-27 18:02:05 +00:00
feat(challenge-md): Add initial markdown challenge files 2018-09-30 22:01:58 +00:00			`Let A(n) be the average of the values of lcm(n,i) for 1≤i≤n.`

Feat: add new Markdown parser (#39800) and change all the challenges to new `md` format. 2020-11-27 18:02:05 +00:00			`E.g: A(2)=(2+2)/2=2 and A(10)=(10+10+30+20+10+30+70+40+90+10)/10=32.`
feat(challenge-md): Add initial markdown challenge files 2018-09-30 22:01:58 +00:00
Feat: add new Markdown parser (#39800) and change all the challenges to new `md` format. 2020-11-27 18:02:05 +00:00			`Let S(n)=∑A(k) for 1≤k≤n. S(100)=122726.`
feat(challenge-md): Add initial markdown challenge files 2018-09-30 22:01:58 +00:00
			`Find S(99999999019) mod 999999017.`

Feat: add new Markdown parser (#39800) and change all the challenges to new `md` format. 2020-11-27 18:02:05 +00:00			`# --hints--`
feat(challenge-md): Add initial markdown challenge files 2018-09-30 22:01:58 +00:00
Feat: add new Markdown parser (#39800) and change all the challenges to new `md` format. 2020-11-27 18:02:05 +00:00			`euler448()` should return 106467648.
feat(challenge-md): Add initial markdown challenge files 2018-09-30 22:01:58 +00:00
Feat: add new Markdown parser (#39800) and change all the challenges to new `md` format. 2020-11-27 18:02:05 +00:00			```js
			`assert.strictEqual(euler448(), 106467648);`
feat(challenge-md): Add initial markdown challenge files 2018-09-30 22:01:58 +00:00			```

Feat: add new Markdown parser (#39800) and change all the challenges to new `md` format. 2020-11-27 18:02:05 +00:00			`# --seed--`
feat(challenge-md): Add initial markdown challenge files 2018-09-30 22:01:58 +00:00
Feat: add new Markdown parser (#39800) and change all the challenges to new `md` format. 2020-11-27 18:02:05 +00:00			`## --seed-contents--`
feat(challenge-md): Add initial markdown challenge files 2018-09-30 22:01:58 +00:00
			```js
			`function euler448() {`
fix: remove Good luck! comment from challenge seed code (#39575) 2020-09-15 16:57:40 +00:00
feat(challenge-md): Add initial markdown challenge files 2018-09-30 22:01:58 +00:00			`return true;`
			`}`

			`euler448();`
			```

Feat: add new Markdown parser (#39800) and change all the challenges to new `md` format. 2020-11-27 18:02:05 +00:00			`# --solutions--`
feat(challenge-md): Add initial markdown challenge files 2018-09-30 22:01:58 +00:00
			```js
			`// solution required`
			```