var n,i,j,k:longint;
    f:text;

function cmmdc(a,b:longint):integer;
var r:integer;
begin
  repeat
    r:=a mod b;
    a:=b;
    b:=r;
  until r=0;
  cmmdc:=a;
end;

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