freeCodeCamp/curriculum/challenges/english/10-coding-interview-prep/project-euler/problem-432-totient-sum.english.md

id, challengeType, title, forumTopicId

id	challengeType	title	forumTopicId
5900f51e1000cf542c510030	5	Problem 432: Totient sum	302103

Description

Let S(n,m) = ∑φ(n × i) for 1 ≤ i ≤ m. (φ is Euler's totient function) You are given that S(510510,106 )= 45480596821125120.

Find S(510510,1011). Give the last 9 digits of your answer.

Instructions

Tests

tests:
  - text: <code>euler432()</code> should return 754862080.
    testString: assert.strictEqual(euler432(), 754862080);

Challenge Seed

function euler432() {
  // Good luck!
  return true;
}

euler432();

Solution

// solution required