note 86281 modified in function.rand by danbrown

A function to generate numbers of any length which contain  no identical digits side-by-side. i.e. 112233


<?php
function randomNumber($number_of_digits=null){
	for($x=0;$x<$number_of_digits;$x++){
		while(substr($num,strlen($num)-1,strlen($num)) == $r) $r = rand(0,9); 
		$new_number .= $r;
	}
	return $new_number;
}
?>

echo randomNumber(9);

// Output: 875438104

--was--
A function to generate numbers of any length which contain  no identical digits side-by-side. i.e. 112233

function randomNumber($number_of_digits=null){
	for($x=0;$x<$number_of_digits;$x++){
		while(substr($num,strlen($num)-1,strlen($num)) == $r) $r = rand(0,9); 
		$new_number .= $r;
	}
	return $new_number;
}

echo randomNumber(9);

// Output: 875438104

http://php.net/manual/en/function.rand.php