custom relation

Array ( [0] => 13730 [1] => 13733 [2] => 13734 [3] => 16596 [4] => 17003 [5] => 17121 [6] => 17462 [7] => 19632 [8] => 20179 [9] => 20211 [10] => 21029 [11] => 22217 [12] => 23320 [13] => 23352 [14] => 23395 [15] => 23397 [16] => 2428643 )