const
  fi = 'pairs.in';
  fo = 'pairs.out';

var
  f : text;
  m : array [1..100000] of longword;
  n,i,j : longword;

  a,b : longword;
  k : longword = 0;

begin
  assign(f,fi);
  reset(f);
  read(f,n);
  for i:=1 to n do
    read(f,m[i]);
  close(f);

  for i:=1 to n do
    for j:= i+1 to n do
      begin
        a := m[i];
        b := m[j];
        while b <> 0 do
          if a > b then
            a := a - b
          else
            b := b - a;
        if a = 1 then
          k := k + 1;
      end;

  assign(f,fo);
  rewrite(f);
  write(f,k);
  close(f);
end.