var n, i, j:longint;
    f, g:text;
    t:longint;

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


begin
assign (f, 'fractii.in'); reset (f);
assign (g, 'fractii.out'); rewrite (g);

read (f, n);
for i := 2 to n do
  begin
  for j := 2 to n do
    begin
    if gcd (i, j)=1 then t:=t+1;
    end;
  end;
t:=t+2*n-1;
writeln (g, t);

close (f); close (g);
end.