freeCodeCamp/curriculum/challenges/en/08-coding-interview-prep/project-euler/problem-448-average-least-common-multiple.en.md

id, challengeType, title

id	challengeType	title
5900f52c1000cf542c51003f	5	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.

Instructions

Tests

- text: <code>euler448()</code> should return 106467648.
  testString: 'assert.strictEqual(euler448(), 106467648, ''<code>euler448()</code> should return 106467648.'');'

Challenge Seed

function euler448() {
  // Good luck!
  return true;
}

euler448();

Solution

// solution required