#include <iostream>
#include <fstream>

using namespace std;

ifstream f("fractii.in");
ofstream g("fractii.out");


int main()
{
    int n;
    f>>n;
    int k=2*n-1;
    for(int i=2;i<n;i++)
    {
            for(int j=i;j<=n;j++)
            {
                int a=i;
                int b=j;
                while(b!=0)
                {
                    int r=a%b;
                    a=b;
                    b=r;
                }
                if( a==1 )
                    k=k+2;
            }
    }
    g<<k;
    return 0;
}