#include <fstream>

using namespace std;

fstream f("fractii.in");
ofstream g("fractii.out");

int cmmdc(int a, int b)
{
    return b?cmmdc(b,a%b):a;
}

int main()
{
    int n, s=0l;
    f>>n;
    for(int i=4; i<=n; i++)
        for(int j=2; j<i; j++)
                s += cmmdc(i,j)!=1?2:0;
    g<<(n-1)*(n-2) - s + 2*n - 1;
    return 0;
}