#include <iostream>
#include <fstream>
using namespace std;

int cmmdc(int a,int b)
{
     int r;
     while (b!=0)
     {
         r=a%b;
         a=b;
         b=r;
     }
     return a;
}

int main()
{
    ifstream f("fractii.in");
    ofstream g("fractii.out");
    int N,rez=0,p=1,q=2;
    f>>N;
    while(q<=N)
    {
        while(p<q)
        {
            if(cmmdc(p,q)==1)
                rez++;
            p++;
        }
        p=1;
        q++;
    }
    rez=2*rez+1;
    g<<rez;

    f.close();
    g.close();
}