#include <iostream>
#include <fstream>
using namespace std;
int cmmdc(int a, int b){
    int r;
   do{
        r=a%b;
        a=b;
        b=r;
    }while(r!=0);
    return a;
}
int main()
{
    ifstream f("fractii.in");
    ofstream g("fractii.out");
    int n;
    int s=0;
    f>>n;
    for(int i=1;i<=n;i++){
        for(int j=1;j<=n;j++)
            if(i==j && i!=1)
            if(cmmdc(i,j)==1) s++;

    }
    g<<s;
    return 0;
}