Austrian zebra divides 180 chess pieces into several parts on average, and the number of pieces in each part cannot be less than 7 or more than 25. How many different division methods are there in total?
奥斑马将180颗棋子平均分成若干份，每份的颗数不得少于7颗，也不能多于25颗，则共有多少种不同的分法．
<result>6</result>