#include <iostream>
#include <bits/stdc++.h>

using namespace std;

ifstream fin("fractii.in");
ofstream fout("fractii.out");

int cmmdc(int a, int b)
{
    if (b == 0)
        {
            if (a == 1)
                return 0;
            else
                return a;
        }
    else
        return cmmdc(b, a % b);
}

int Fractii(int n)
{
    int nr = 0;
    for (int i = 1,j = 1; i <= n; i++)
            if (cmmdc(i,j) > 1)
                nr++;
    //cout << nr;
    return n*n-nr;

}

int main()
{
    int n;
    fin >> n;
    fout << Fractii(n);
    return 0;
}