Program cascaval_e;
uses crt;
Var o,n:longint;
s:int64; f:text;

Function cmmdc(a,b:longint):longint;
Var r:longint;
Begin
r:=1;
while r<>0 do
        begin
        r:=a mod b; a:=b; b:=r; end;
cmmdc:=a;
end;

Function indiv(a:longint):longint;
Var i:longint;
Begin
i:=0; indiv:=0;
repeat inc(i);
       if cmmdc(a,i)=1 then inc(indiv);
until i=n;
end;

Begin
clrscr;
assign(f,'fractii.in'); reset(f); readln(f,n) ;s:=0; close(f);
for o:=1 to n do s:=s+indiv(o);
assign(f,'fractii.out'); rewrite(f); writeln(f,s); close(f);
end.