array(4) {
  [0]=>
  int(1)
  [1]=>
  int(2)
  [2]=>
  int(3)
  [3]=>
  int(4)
}
array(4) {
  [0]=>
  int(2)
  [1]=>
  int(4)
  [2]=>
  int(6)
  [3]=>
  &int(8)
}
0 => 2 Array
(
    [0] => 2
    [1] => 4
    [2] => 6
    [3] => 2
)
1 => 4 Array
(
    [0] => 2
    [1] => 4
    [2] => 6
    [3] => 4
)
2 => 6 Array
(
    [0] => 2
    [1] => 4
    [2] => 6
    [3] => 6
)
3 => 6 Array
(
    [0] => 2
    [1] => 4
    [2] => 6
    [3] => 6
)