Untitled

How can I find a previously unknown pattern in an array using PHP?
$arr=array(1,1,3,5,1,1,3,5,1,1,3,5,1,1,3,5);
$p=array();
for($i=0;$i<count($arr);$i++){
    $tmp=$arr[$i].'';
    for($j=$i;$j<count($arr);$j++){
        $tmp.=','.$arr[$j];
        if(isset($p[$tmp])){
            //nope
        }
        else{
            //nice try
        }
    }

}
foreach($p as $key=>$val){
    if($val>1)
    echo "The patter: $key appeared $val times<br>";
}

$arr = array(1,1,3,5,1,1,3,5,1,1,3,5,1,1,3,5,1,1,3,5);
$data = implode('', $arr);
for($i=0; $i < count($arr)-1; $i++){
$pattern .= $arr[$i];
if (substr_count($data ,$pattern) !=1)
echo $pattern . ' found '.substr_count($data ,$pattern). ' times<br />';
}