my $n = shift;
sub plustwo_iter {
  my $val = 1;
  return sub  {
    $val +=2;
    return $val;
  }
}

my $p = plustwo_iter();

my $loop = [[0..1], (sub {[$_+1..&$p]}) x ($n-2)];

my $iter = NestedLoops($loop);
while (my @list = $iter->()) {
  output(@list);
}