#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;l<=max/2&&max!=1;l++) if(c%l==0&&k%l==0) v=0;

}

if(v==1) ori++;


}}
    out<<ori; 
return 0;
}