#include<fstream>
using namespace std;
int a,b,s,i,j;
int cmmdc(int a,int b)
{
    if(b==0)
    {
        return a;
    }
    else
    {
        return cmmdc(b,a%b);
    }
}
int main()
{
     ifstream fin("fractii.in");
    ofstream fout("fractii.out");
    fin>>a;
    s=a;
    for(i=2;i<=a;i++)
    {
        for(j=1;j<=a;j++)
        {
            if(i%j!=0 || j%i!=0)
            {
                s=s+1;
            }
        }
    }
    fout<<s;
    fin.close();
    fout.close();
    return 0;
}