#include <iostream>
#include <fstream>

using namespace std;


int cmmdc(int a,int b)
{
    if(a==0 || b==0)
        return a+b;
    if(a>b)
        return cmmdc(a%b,b);
        else
        return cmmdc(a,b%a);
}

int main()
{
    int n,x,y,s=0;

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

    f>>n;
    x=n;
    y=n;

    if(n>1)
    {
        while(y>=2)
        {
            while(x>=2)
            {
                    if(cmmdc(x,y)==1)
                    s++;
            x--;
            }
            x=n;
            y--;

            }

        g<<s+2*(n-1)+1;
    }
    else
        g<<0;
    return 0;

}