program Project2;
{$APPTYPE CONSOLE}
uses
  SysUtils;

var i,j,n,ans: longint;
    inp,outp: text;
    a: array[1..20000000] of integer;
function NSD(var m,b: longint): longint;
label 1;
var l,k: integer;
    c: longint;
begin
   k:=m;
   l:=b;
   if k=l then
      begin
         NSD:=k;
         goto 1;
      end;
   while (k<>0)and(l<>0)do
      if k>l then
         k:=k-l
      else
         l:=l-k;
   if k=0 then NSD:=l
      else NSD:=k;
1:
end;
begin
   assign(inp,'pair.in');
   assign(outp,'pair.out');
   reset(inp);
   rewrite(outp);
   readln(inp,n);
   ans:=n;
   for i:=1 to n-1 do
      for j:=i+1 to n do
         if j mod i=0 then inc(ans);

   writeln(outp,ans);
   close(inp);
   close(outp);
end.