#include <iostream>
#include <fstream>
#include <math.h>
using namespace std;
ifstream f("fractii.in");
ofstream g("fractii.out");
int n,i,j,ci,cj,nr,r;
int main()
{f>>n;nr=2*n-1;
  for (i=2;i<=n-1;i++)
   for (j=i+1;j<=n;j++)
   {ci=i;cj=j;
   while (cj)
   {r=ci%cj;
   ci=cj;
   cj=r;
   }
   if (ci==1)nr+=2;
   }
   g<<nr;
   f.close();
   g.close();
    return 0;
}