#include<fstream>
using namespace std;
int cmmdc(int, int);

int main()
{
    int n,i,j,k;
    ifstream cin("fractii.in");
    ofstream cout("fractii.out");
    cin>>n;
    k=2*n-1;
    for(i=2;i<=n;i++)
        for(j=2;j<=n;j++)
            if(cmmdc(i,j)==0)
                k++;
cout<<k;

return 0;
}

int cmmdc(int a, int b)
{
    while(a*b!=0)
    {
        if(a>b)
        a=a%b;
        else
        b=b%a;
    }
if(a+b!=1)
return a+b;
else
return 0;
}