<section id="description">
<p>Euler's Totient function, φ(n) [sometimes called the phi function], is used to determine the number of numbers less than n which are relatively prime to n. For example, as 1, 2, 4, 5, 7, and 8, are all less than nine and relatively prime to nine, φ(9)=6.</p><p>n
Relatively Prime
φ(n)
n/φ(n)
2
1
1
2
3
1,2
2
1.5
4
1,3
2
2
5
1,2,3,4
4
1.25
6
1,5
2
3
7
1,2,3,4,5,6
6
1.1666...
8
1,3,5,7
4
2
9
1,2,4,5,7,8
6
1.5
10
1,3,7,9
4
2.5</p>
<p>It can be seen that n=6 produces a maximum n/φ(n) for n ≤ 10.
Find the value of n ≤ 1,000,000 for which n/φ(n) is a maximum.</p>
</section>

function euler69() {
  // Good luck!
  return true;
}

euler69();


index

Проблема 69 крупнейшим Totient

Problem 69: Totient maximum

<code>euler69()</code> should return 510510.