var i,j,x,n:longint;

function cmmdc(a,b:longint):longint;
begin
 if b=0 then cmmdc:=a
        else cmmdc:=cmmdc(b,a mod b);
end;

begin
assign(input,'fractii.in');reset(input);
assign(output,'fractii.out');rewrite(output);
 readln(n);
 x:=n*2-1;
 for i:=2 to n do
  for j:=2 to n do
   if (i<>j) or ((i mod 2<>0) and (j mod 2=0)) then if cmmdc(i,j)=1 then inc(x);
write(x);
close(input);close(output);
end.