#include <iostream>
#include <fstream>
using namespace std;
fstream fin("fractii.in",ios::in);
fstream fout("fractii.out",ios::out);

int n;

bool cmmdc(int a,int b){
    while(b){
        int r = a%b;
        a = b;
        b = r;
    }
    if(a == 1)
        return false;
    return true;
}

unsigned long  rezolv(){
    long long  number = n;
    for(int i=2;i<=n;i++)
        {for(int j=1;j<=n;j++)
        if(cmmdc(i,j) == false)
            /*cout << i << "/" << j << "\t";
            cout << "\n";*/
            number++;
            }
    return number;
}
int main()
{
  //  while(true){
            fin >> n;
    fout << rezolv();
   // cout << "\n\n";}
    return 0;
}