Hi i want to loop through an setup array skipping an index at a time

e.g. 1,2,3,4

but looping 1,3,5,7 but the catch is when looping i want to display 2,4,6,8.

for example

$array = array("1", "top admin", "2", "middle admin", "3", "mod").

foreach array = $value+2
{
echo "$value . "is number " . array(i+1);
}

sorry if this is quick but doing it on borrowed time. any ideas?