var n,s,i,j:longint;

function cmmdc(a,b:longint):longint;
var r:longint;
begin
 r:=a mod b;
 while r<>0 do begin
  a:=b;
  b:=r;
  r:=a mod b;
 end;
cmmdc:=b;
end;

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