#include <iostream>
#include <fstream>
using namespace std;
ifstream fin("fractii.in");
ofstream fout("fractii.out");
int n,i,j,x,v[1000005];
int cmmdc(int a, int b)
{
    if(b)
      return cmmdc(b,a%b);
    return a;
}
int main()
{

    long long nr=0;
    int a,b;
    fin>>n;
    for(i=1; i<=n; i++)
        for(j=i; j<=n; j++)
        {
            a=i;
            b=j;
            if(cmmdc(a,b)==1)
                nr+=2;
        }
    fout<<nr-1;
}