#include<fstream>   
using namespace std;   
int main(){   
    fstream in("fractii.in", ios::in);   
    fstream out("fractii.out", ios::out);   
    unsigned int x,ori;   
    in>>x;   
    ori=x;   
    bool v=1; unsigned int max;   
for(int c=2;c<=x;c++){    
           
ori++;    
//cout<<"ori creste la c="<<c<<" si k="<<1<<" ori devine "<<ori<<endl;    
for(int k=2;k<=x;k++){    
v=1;   
if(c%k==0||k%c==0) { v=0;    
} else {   
  
if(c<k)max=c;else max=k;    
  
for(int l=2;max!=1&&l<=max/2;l++) if(c%l==0&&k%l==0) v=0;   
  
}   
  
if(v==1) ori++;   
  
  
}}   
    out<<ori;    
return 0;   
}