var f,g:text;j,k,i,s,n:longint;
function asd(i:longint):longint;
var j,k,q,h:longint;
begin
h:=0;
for j:=1 to n do
  begin
  for k:=1 to i do
  if (j mod k=0) and (i mod k=0) then q:=k;
  if q=1 then h:=h+1;
  end;
asd:=h;
end;
function prim (i:longint):boolean;
var j:longint;
begin
prim:=true;
for j:=1 to i-1 do
if i mod j=0 then prim:=false;
end;
begin
assign (f,'fractii.in');
reset (f);
assign (g,'fractii.out');
rewrite (g);
read (f,n);
s:=n+n-n div 2+n-n div 3;
for i:=4 to n do
begin
if prim(i) then
           else s:=s+asd(i);
end;
write (g,s);
close (g);
end.