#include <fstream>

using namespace std;
ifstream in("fractii.in");
ofstream out("fractii.out");
int n,i,j,s;
int Pi[1000001];
int main()
{
    in>>n;
    for(i=1;i<=n;i++)
    Pi[i]=i-1;
    Pi[1]=1;
    for(i=2;i<=n;i++)
        for(j=i*2;j<=n;j++)
            Pi[j]=Pi[j]-Pi[i];
            for(i=1;i<n;i++)
            s+=Pi[i];
            out<<s*2-1;
            in.close();
            out.close();
    return 0;
}