var f,g:text;
    nr,i,j,n,c:integer;
function cmmdc(a,b:integer):integer;
 begin
 while a<>b do begin
 if a>b then a:=a-b
        else b:=b-a;
 end;
 cmmdc:=a;
 end;
 begin
  assign(f,'fractii.in');reset(f);
  assign(g,'fractii.out');rewrite(g);
  readln(f,n);nr:=0;
  for i:=1 to n do begin c:=i;
  for j:=1 to n do
  if cmmdc(c,j)=1 then nr:=nr+1;end;
  write(g,nr);
 close(f);
 close(g);
end.