var f,g:text;

    N,P,Q,fractii:byte;
begin

assign(f,'fractii.in');
reset(f);
assign(g,'fractii.out');
rewrite(g);

read(f,N);

for p:=1 to N do
begin

for q:=2 to N do
begin

if p mod q <> 0 then inc(fractii);

end;


end;

write(g,fractii+N);

close(f);
close(g);

end.