function cmmdc(m,n:longint):longint;
 var r:longint;
begin
 r:a mod b;
 while r<>0 do begin
 a:=b;  b:=r;
 r:=a mod b;
 end;
 cmmdc:=b;
 end;

  var n,i,j,c:longint;
   begin
   assign(input,'fractii.in'); reset(input);
   assign(output, 'fractii.out'); rewrite(output);

 readln(n);
 c:=1;
 for i:=1 to n do
  for j:=2 to n do if cmmdc(i,j)=1 then c:=c+1;

  write(c*2);

  close(input);
  close(output);
  end.