program fract;
var i,j,n,s:longint;
f:text;
begin
 assign(f,'fractii.in'); reset(f);
 readln(f,n);
 close(f);
 s:=n;
 for i:=2 to n do
  for j:=1 to n do begin
  if j=1 then s:=s+1;
   if (i>j) and (i mod j<>0) then s:=s+1;
   if (i<j) and (j mod i<>0) then s:=s+1;
  end;
 assign(f,'fractii.out'); rewrite(f);
 write(f,s);
 close(f);
end.