The TV station wants to broadcast a 30-episode TV series. If the number of episodes scheduled to be broadcast each day is not equal to each other, how many days can the TV series be played at most?
电视台要播放一部30集电视连续剧，如果要求每天安排播出的集数互不相等，该电视剧最多可以播放多少天．
<result>7</result>