/***************************************************************************
 *   Copyright (C) 2008 by cata,,,   *
 *   cata@cata-laptop   *
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 *   This program is distributed in the hope that it will be useful,       *
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
 *   GNU General Public License for more details.                          *
 *                                                                         *
 *   You should have received a copy of the GNU General Public License     *
 *   along with this program; if not, write to the                         *
 *   Free Software Foundation, Inc.,                                       *
 *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
 ***************************************************************************/


#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <iostream>
#include <cstdlib>
#include<fstream>
using namespace std;

ifstream f("/home/cata/te/src/fractii.in");
ofstream g("/home/cata/te/src/fractii.out");

long cmmdc(long long a, long long b)
{
while(b!=0)
 {long long r = a%b;
 a=b;
 b=r;
}
return a;
}

int main(int argc, char *argv[])
{
long long n, a,b,nr=0;
if(f.is_open())
f>>n;
else cout<<"er";

for(a=2;a<=n;a++)
 for(b=a+1;b<=n;b=b+1)
 if( cmmdc(a,b)==1)
	{//cout<<a<<" "<<b<<" "<<cmmdc(a,b)<<endl;
nr=nr+2;}
g<<nr+2*n-1;
f.close();
g.close();
  return EXIT_SUCCESS;
}