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

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+---
+id: 5900f51e1000cf542c510030
+challengeType: 5
+title: 'Problem 432: Totient sum'
+forumTopicId: 302103
+---
+
+## Description
+<section id='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.
+</section>
+
+## Instructions
+<section id='instructions'>
+
+</section>
+
+## Tests
+<section id='tests'>
+
+```yml
+tests:
+  - text: <code>euler432()</code> should return 754862080.
+    testString: assert.strictEqual(euler432(), 754862080);
+
+```
+
+</section>
+
+## Challenge Seed
+<section id='challengeSeed'>
+
+<div id='js-seed'>
+
+```js
+function euler432() {
+
+  return true;
+}
+
+euler432();
+```
+
+</div>
+
+
+
+</section>
+
+## Solution
+<section id='solution'>
+
+```js
+// solution required
+```
+
+</section>