#include<iostream>
#include<fstream>
using namespace std;
ifstream f("fractii.in");
ofstream g("fractii.out");
int nr=0;
int cmmdc(int a , int b)
{
    while(a!=b)
    {
        if(a>b)
            a-=b;
        else
            b-=a;
    }
    return a;
}
void numarare(int a, int b,int n)
{

   while(a<=n&&b<=n)
    {
        if(a==n)
            numarare(1,b+1,n);
        if(cmmdc(a,b)==1)
            nr++;
		a++;
    }

}
int main()
{
    int n;
    f>>n;
    numarare(1,1,n);
    g<<nr;
    return 0;
}