Please Help With Pyramid Output Of Numbers

[noob_prog]

I'm trying to modify a script to output the numbers in a pyramid form like this :

1

23

456

This is the code I'm trying to modify

<?php
for($a = 1; $a < 10; $a++){
for ($b = 1; $b <= $a; $b++)	 {	
 echo $b;	 }	
 echo "<br>";
}
?>

The problem with it is that it begins every line with 1. Like

1

12

123

I tried a bit but I'm unable to modify it correctly. I'm completely new to PHP. Please help me out. I have been working on it for some time now.

Thanks,

Adrian

[Barand]

for($a = 1, $n = 1; $a < 10; $a++){
   for ($b = 1; $b <= $a; $b++,$n++)	 {	  
	 echo $n. ' ';
 }	  
 echo "<br>";
}

Edited October 31, 2012 by Barand