Program fractii;
Var f:text;
    n,s,i,j:longint;
function prime_intre_ele(a,b:longint):boolean;
var r:longint;
begin
 repeat
  r:=a mod b;
  a:=b;
  b:=r;
 until(r=0);
 prime_intre_ele:=false;
 if a=1 then prime_intre_ele:=true;
end;
Begin
  assign(f,'fractii.in');
  reset(f);
  readln(f,n);
  close(f);
  s:=2*n-1+2*n-4;
  for i:=2 to n-2 do
     for j:=i+2 to n do
        if not((i mod 2=0) and (j mod 2=0)) then
          if j mod i>0 then
            if prime_intre_ele(i,j) then s:=s+2;
  assign(f,'fractii.out');
  rewrite(f);
  Writeln(f,s);
  close(f);
End.