a[0]={1,2,3};
a[1]={2,3,4};
**Edit** in a[2] from a[2]={4,5};
a[2]={2,4,5};
and more

call_user_func_array('array_intersect',$a);

$intersect = $a[0];
for ($i = 1; $i < count($a); $i++)
{
    $intersect = array_intersect($intersect, $a[$i]);
}

<?php
$array1 = array("a" => "green", "red", "blue");
$array2 = array("b" => "green", "yellow", "red");
$result = array_intersect($array1, $array2);
print_r($result);
?>

Array
(
    [a] => green
    [0] => red
)