#include <fstream>
#include <iostream>

using namespace std;

int main()
{
    ifstream in("fractii.in");
    ofstream out("fractii.out");
    int n,p,q,f=0,a,b,r;
    in>>n;
   f=n;
   if(n%2==1)f+=n/2+1;
   else f+=n/2;
    for(p=3;p<=n;++p)
    {
        for(q=1;q<=n;++q)
        {
            //if(p%2==0&&q%2==0)break;

            b=q;
            a=p;
            while(r=a%b)
            {
                a=b;b=r;
            }
            if(b==1)
            {
                ++f;
            //cout<<p<<"/"<<q<<endl;
            }
        }
    }
    out<<f;
}