$target = 479179/526680;
$targetmax = $target + 0.000000001;
$targetmin = $target - 0.000000001;
$xsum = .0;
$res = array();

function doone ($start,$depth){
    $alpha = array (
    1 => 'a', 2=>'b', 3=>'c', 4=>'d', 5=> 'e', 6=>'f',7=>'g', 8=>'h',
    9 => 'i', 10=>'j', 11=>'k', 12=>'l', 13=>'m', 14=>'n',15=>'o', 16=>'p',
    17=> 'q', 18=>'r', 19=>'s', 20=>'t', 21=>'u', 22=>'v', 23=>'w',24=>'x',
    25=>'y',26=>'z');

    global $xsum, $res,$target,$targetmax,$targetmin;
    foreach (range($start, 26) as $a) {
        $m = 1/$a;
            if ($xsum + $m > $targetmax){
                continue;
            }
            $xsum +=$m;
            $res[]=$a;
            if ($depth == 9){
                if ($targetmin < $xsum && $xsum < $targetmax){
                    foreach ($res as $b) {
                        echo $alpha[$b];
                        }
                        echo "\n";
                    }
                } else {
                    doone($a,$depth+1);
                }
                $xsum -= $m;
                array_pop ($res);
        }
}
doone(2,1);