gistfile1.txt

/**
 * codekata
 *
 * @param null $number1
 * @param null $number2
 * @param null $number3
 * @param array $notIn
 * @return array
 */
function generator($number1 = null, $number2 = null, $number3 = null, $notIn = [])
{
    $arr = [];
    for ($i = 102; $i < 987; $i++) {
        $str = (string)$i;
        if ((in_array($str[0], $notIn) || in_array($str[1], $notIn) || in_array($str[2], $notIn))
            || $str[0] == $str[1] || $str[0] == $str[2] || $str[1] == $str[2]
        ) {
            continue;
        }
        if ((is_null($number1) || $str[0] == $number1) &&
            (is_null($number2) || $str[1] == $number2) &&
            (is_null($number3) || $str[2] == $number3)
        ) {
            $arr[] = $i;
        }
    }
    return $arr;
}

$arr = generator(null, null, 6, [0,1,2,3, 4, 5,7]);
print_r($arr);
die;