set_time_limit(0);
  $cas1=mktime(); echo "<h3>Start: ".date("d.m.Y G:i:s T",$cas1)."<br>i=1</h3>";
  function power($i) {
    switch($i):
      case 0: return 0;
      case 1: return 1;
      case 2: return 4;
      case 3: return 27;
      case 4: return 256;
      case 5: return 3125;
      case 6: return 46656;
      case 7: return 823543;
      case 8: return 16777216;
      case 9: return 387420489;
    endswitch;
  }

  for ($i=1;$i<=999999999999;$i++) {
    $nums = str_split($i,1);
    $sum=0;
      foreach ($nums as $key => $value) {
        $sum=$sum+power($value);
        if ($sum>$i+5) { break; }
      }
      if ($sum==$i) { $results[$i]= $sum; }
      elseif ($sum>($i-5) and $sum<($i+5)) { $close[$i]=$sum; }
  }
   $cas2=mktime();
   $cas=($cas2-$cas1);
   $help = explode(".",($cas/(60*60)));
   $hours = $help[0];
   $help2 = explode(".",(($cas-($hours*60*60))/60));
   $mins = $help2[0];
   $secs = $cas-($hours*60*60)-($mins*60);
   $x = $hours.":".$mins.":".$secs;
   echo "<h3>End: ".date("d.m.Y G:i:s T",$cas2)."<br>i=".$i."<br>The script ran for ".$x."</h3>";
   echo "Exact: ";
   foreach ($results as $key => $value) {
     echo $key."=>".$value."; ";
   }
   echo "<br>Close: ";
    foreach ($close as $key => $value) {
     echo $key."=>".$value."; ";
   }