#include <cstdlib>
#include <iostream>
#include <fstream>
using namespace std;

int ValidFra(int a,int b)
{   
 if (a==b) return 0;
 if (a>b) for(int i=2;i<=b;i++) if (a%b==0) return 0;
 if (b>a) for(int i=2;i<=a;i++) if (b%a==0) return 0;
 return 1;    
}

int main(int argc, char *argv[])
{
    int nrFractii=1;
    int n;
    freopen("fractii.in","r",stdin);
    scanf("%i",&n);
    for (int i=1;i<=n;i++)
       for (int j=1;j<=n;j++) if (ValidFra(i,j)==1) nrFractii++;  
    freopen("fractii.out","w",stdout);      
    printf("%i",nrFractii);
    fclose(stdin);
    fclose(stdout);
return 0;    
}