#include<iostream>
#include<fstream>
#include<stdio.h>
using namespace std;
unsigned long long int iteratii=0;
inline int cmmdc(int a, int b)
{
    unsigned r;
    if (a>b)
    {
        r=a%b;
        while(r)
        {
            a=b;
            b=r;
            r=a%b;
            iteratii++;
        }
        return b;
    }
    else
    {
        r=b%a;
        while(r)
        {
            b=a;
            a=r;
            r=b%a;
            iteratii++;
        }
        return a;
    }
}
int main()
{
    unsigned long int n,i=0,j,nr_fractii=0;
    fstream f("fractii.in",ios::in);
    fstream f2("fractii.out",ios::out);
    f>>n;
    //cout<<cmmdc(13,39);
    //cout<<"1/1 1/2 1/3 1/4 1/5 1/6 ";
    for (i=2;i<=n;i++)
    {
        /*if (i%2==1)
        {
            //cout<<i<<"/1 ";
            for (j=2;j<=n;j++)
            {
                if (cmmdc(i,j)==1)
                {
                    //cout<<i<<"/"<<j<<" ";
                    //printf("%d/%d ",i,j);
                    nr_fractii++;
                    iteratii++;
                }
            }
        }
        else
        {
            for (j=1;j<=n;j+=2)
            {
                if (cmmdc(i,j)==1)
                {
                    //cout<<i<<"/"<<j<<" ";
                    //printf("%d/%d ",i,j);
                    nr_fractii++;
                    iteratii++;
                }
            }
        }*/
        for (j=2;j<=n;j++)
        {
            if (cmmdc(i,j)==1)
            {
                nr_fractii++;
            }
        }
    }
    cout<<"Nr fractii: "<<nr_fractii+n+n-1<<"\n";
}