var
 f:text;
 n,p,q,k:longint;

 function ire(x,y:longint):longint;
   begin
    if x mod y=0 then ire:=y
    else
    ire:=ire(y,x mod y);
   end;
 begin
  assign(f,'fractii.in');
  reset(f);
  readln(f,n);
  close(f);}
  {randomize;
  n:=random(9999)+1 ;}
  {n:=1000000;}
  assign(f,'fractii.out');
  rewrite(f); k:=2*n-1;
  for p:=2 to n do
   for q:=2 to n do
    begin

    if ire(p,q)=1 then inc(K);
    end;
   write(f,k);
   close(f);
   end.