#include<iostream.h>
#include<fstream.h>
long a,b,N;
long long r=0;
int prime(long a, long b)
{
    while(a!=b){                
                if(a<b) {
                        if(a==1) b=1;
                        else b=b-a;
                        }
                else {
                     if(b==1) a=1;
                     else a=a-b;
                     }
               }
    if (a==1) return 1;              
    else return 0;
}
int fractii(long N)
{
    for(a=1;a<N;a++){
                     for(b=a+1;b<=N;b++){
                                         if (prime(a,b)==1) r=r+1;
                                         }
                     }
    return r*2+1;
}
int main()
{     
    ifstream in("fractii.in");
    ofstream out("fractii.out");
    in>>N;
    out<<fractii(N); 
    in.close();       
    out.close();
}