#include <iostream>
#include <fstream>
using namespace std;
ifstream f("fractii.in");
ofstream g("fractii.out");
int cmmdc(int a,int b)
{
    if(b==0) return a;
    else return cmmdc(b,a%b);
}
int main()
{
    long long n,c,i=0,j=0;
    f>>n; c=n;
    for(i=1;i<=n;i++)
    {
        for(j=2;j<=n;j++)
        {
            if(cmmdc(i,j)==1){ c++;
            }
        }
    }
    g<< c;
    return 0;
}