type tip=1..1000000;
var
    n,p,q:tip;
    nr:longint;
    f,g:text;
    function cmmdc(p,q:tip):tip;
    begin
            if p=q then cmmdc:=q
              else if p>q then cmmdc:=cmmdc(p-q,q);
                 if q>p then cmmdc:=cmmdc(p,q-p);
    end;
begin
         assign(f,'fractii.in');
         reset(f);
         read(f,n);
         close(f);
        writeln;
        writeln;
         p:=2;
         q:=1;
         nr:=2*n-1;

     while p<=n do
       begin
      q:=2;
    while q<=n do
       begin
   if cmmdc(p,q)=1 then nr:=nr+1;
    q:=q+1;
        end;
     p:=p+1;
       end;
  assign(g,'fractii.out');
  rewrite(g);
  write(g,nr);
  close(g);
end.