#include <fstream>
using namespace std;
ifstream f("fractii.in");
ofstream g("fractii.out");
int main()
{
    int n,i,j,x,y,nr=0,r;
    f>>n;
    nr=1;
    for(i=1;i<=n-1;i++)
        for(j=i+1;j<=n;j++)
    {
        x=i;
        y=j;
        while(y)
        {
            r=x%y;
            x=y;
            y=r;
        }
        if(x==1) nr+=2;
    }
    g<<nr;
}