<?php
function odd($limit){
$row=1;
$current_number=1;
while($current_number<=$limit){
for($i=1;$i<=$row;$i++){
echo $current_number." ";
$current_number=$current_number+2;//incrementing numbers by 2 if you want to increment by 1 i.e print all numbers replace 2 by 1
}
$row++;
echo "<br/>";//for new line
}
}
odd(20);
?>