#include<fstream>
int cmmdc(unsigned long m, unsigned long n){ 
      if(!n)return m; 
      return cmmdc(n,m%n); 
}
int main(){
    ifstream f("fractii.in");
    ofstream g("fractii.out");
    
    unsigned long n,i,j,k;
    
    f>>n;
    if(n==1)k=1;
    else
    if(n==2)k=3;
    else{
    k=2*n-1;
    for(i=2;i<=n;i++)
      for(j=i+1;j<=n;j++)
         if(cmmdc(i,j)==1) k+=2;
    }
    
    g<<k;
    f.close();
    g.close();
    return 0;
}