#include <iostream>

using namespace std;

unsigned P, Q;

unsigned euclid(unsigned P, unsigned Q)
{
    unsigned d;
    while (Q)
    {
        d=P%Q;
        P=Q;
        Q=d;
    }
    return (P==0 || P==1);
}

int main()
{
    unsigned N;
    //ifstream fin("fractii.in");
    cin>>N;
    //fin.close();
    unsigned c=0;
    for (P=1; P<=N-1; P++)
        for (Q=P; Q<=N; Q++)
            if (P/Q!=1 && euclid(P,Q)==1 )
                c++;
            cout<<c*2+1;
    //fstream fout("fractii.out");
    //fout<<c;
    //fout.close();
    return 0;
}