const inp='PT.INP';
outp='PT.OUT';
var t,n,i:longint;
f:text;
//
function kt(x:longint):longint;
begin
if x<>0 then exit(1) else exit(0);
end;
//
begin
assign(f,inp);
reset(f);
read(f,n);
close(f);
t:=0;
for i:=1 to n div 2 do
inc(t,((n-i) div i)+kt(n mod i));
assign(f,outp);
rewrite(f);
write(f,t+1);
close(f);
end.